WCDMA UTRAN Interfaces and Protocol Stacks

1 © NOKIA 3G Mobile Systems.PPT v.0.0.3/ March 2002 / David Soldani

UTRAUTRAUTRAUTRA----FDDFDDFDDFDD Radio CommunicationRadio CommunicationRadio CommunicationRadio Communication

By David Soldani


UTRAN Interfaces and Protocol StacksUTRAN Interfaces and Protocol StacksUTRAN Interfaces and Protocol StacksUTRAN Interfaces and Protocol Stacks


Network ElementsNetwork ElementsNetwork ElementsNetwork Elements and Interfacesand Interfacesand Interfacesand Interfaces

Uu Interface:Uu Interface:Uu Interface:Uu Interface:Transport PlaneTransport PlaneTransport PlaneTransport Plane

Control PlaneControl PlaneControl PlaneControl Plane

User PlaneUser PlaneUser PlaneUser Plane

ProceduresProceduresProceduresProcedures

- WCDMA (Wideband CodeDivision Multiple Access)

- DPDCH and DPCCH Channels

- Optimized, application relatedprotocols suitable for bothpacket and circuit switched

traffic

- RRC Connection Management - Radio Bearer control- RRC connection mobility- Measurement- General procedures

Iub Interface:Iub Interface:Iub Interface:Iub Interface:Transport PlaneTransport PlaneTransport PlaneTransport Plane




- ATM

- Communication Control Ports- Node B Control Ports

- RACH/FACH/DCH Data Portsforming UE Context(s)

- Radio Link (RL) Setup- RL Reconfiguration- RL Addition- RL Deletion

- Power Control Information- Handover Signalling- Measurement Reports

Iur Interface:Iur Interface:Iur Interface:Iur Interface:Transport PlaneTransport PlaneTransport PlaneTransport Plane




- ATM

- RNSAP (SCCP over CCS7 )

- Frame Protocols for DedicatedChannels over ATM

- Radio Link (RL) Setup- RL Reconfiguration- RL Addition- RL Deletion

- Power Control Information- Handover Signalling- Measurement Reports

Iu Interface for CN Packet Domain:Iu Interface for CN Packet Domain:Iu Interface for CN Packet Domain:Iu Interface for CN Packet Domain:Transport PlaneTransport PlaneTransport PlaneTransport Plane




- ATM

- RANAP over CCS7 or IP

- GTP (GPRS TunnelingProtocol) over UDP/IPover AAL5

- Radio Access Bearer Management- SRNC Relocation

- Direct Transfer Procedures(Direct Signalling between UEand the CN Packet Domain)

Iu Interface for CN Circuit Domain:Iu Interface for CN Circuit Domain:Iu Interface for CN Circuit Domain:Iu Interface for CN Circuit Domain:Transport PlaneTransport PlaneTransport PlaneTransport Plane




- ATM

- RANAP over CCS7

- Optimized, applicationrelated protocols overATM AAL2

- Radio Access Bearer Management- SRNC Relocation

- Direct Transfer Procedures(Direct Signalling between UEand the CN Circuit Domain)

Node B Functions:Node B Functions:Node B Functions:Node B Functions:- Modulation

- Rate Matching- Error Protection in Uu Interface- Uu Interface Channelisation- Macro Diversity (Softer Handover)

- RRM: PC, LC, RM

RNC Functions:RNC Functions:RNC Functions:RNC Functions:Radio Resource ManagementRadio Resource ManagementRadio Resource ManagementRadio Resource Management

Telecommunication ManagementTelecommunication ManagementTelecommunication ManagementTelecommunication Management

- Admission Control- Code Allocation (RM)- Load Control

- Power Control- Handover Control (HO)- Macro Diversity (Soft HO)

- Radio Access Bearer (RAB)- RAB - Radio Link Mapping

Transmission ManagementTransmission ManagementTransmission ManagementTransmission Management

Node B

Node B

RNC

RNC

CellCellCellCell is defined by a cell identification (C-ID), Configuration Generation ID, Timing delay (T_Cell), UTRA Absolute Radio Frequency Channel Number (UARFCN), Maximum transmission power, Closed Loop Timing Adjustment Mode and Primary scrambling code


Protocol ArchitectureProtocol ArchitectureProtocol ArchitectureProtocol ArchitecturePlane

EntityEntity

Layer N

Layer N -1

Layer N+1

Primitive = 1...Ninterlayer data

flows

Protocol = 1...NProcedures

SAPSAP

Procedure = 1 ...Nmessages

EntityEntity

Entity Entity

SAP SAP

ELEMENT XELEMENT XELEMENT XELEMENT X(peer or entity)(peer or entity)(peer or entity)(peer or entity)

ELEMENT YELEMENT YELEMENT YELEMENT Y(peer or entity)(peer or entity)(peer or entity)(peer or entity)

Set of defined rules or

procedures

Set of well defined

protocols

Set of different protocols

defined for common purpose

Data exchange between layers

Reference point between subsystems(domains)

Main reasons behind the layered architectureMain reasons behind the layered architectureMain reasons behind the layered architectureMain reasons behind the layered architecture•To handle the architectural complicity in very large communication systems by utilizing layered modelling•To facilitate the system implementation and testing •To support the system evolution by easing the modifications to the existing systems•To support the service vs. system independence•To ensure the system forward and backward compatibility•Cost-efficiency in a large network environment with many NEs•Common reference model (OSI, Open System Interconnection)ProtocolProtocolProtocolProtocolA set of defined rules or procedures and conventions used by a specific layer in order to communicate with a similar peer or entity layer in another NE or subsystemLayerLayerLayerLayerA set of well-defined functionalities or protocols in the context of the overall communication subsystem. A protocol layer can be implemented independentlyPlanePlanePlanePlaneA set of different protocols (including different layer) used for common purposes in a communication system (CCCC----plane, Uplane, Uplane, Uplane, U----Plan, transport planePlan, transport planePlan, transport planePlan, transport plane). A plane can be implemented independentlyService Access PointService Access PointService Access PointService Access PointA reference point between two immediately above and below protocol layers through which the layers can exchange dataInterfaceInterfaceInterfaceInterfaceA well-defined reference point between two subsystems (domains) in which the subsystems exchange information with a fully recognized manner


UTRANUTRANUTRANUTRAN Interfaces Protocol StacksInterfaces Protocol StacksInterfaces Protocol StacksInterfaces Protocol Stacks

xxAP FPs

ALCAP

Transport

Radio Network Layer

Transport Network

Layer

CP (1)

TNCP (2)

UP (3)

TransportTransport

(1) Control Plane: Interface Application Part (RANAP for Iu, RNSAP for Iur, NBAP for Iub) and signalling bearers (ex: SS7, CTP/IP)

UTRANspecificprotocols

(3) User Plane: Frame Protocols (FP) for user data transfer through the interface and the underlying transport protocols

(2) Transport Network Control Plane: Signalling protocol (Access Link Control Application Part) + bearer, for the control of the transport channels in the user plane (ex Q.AAL2)


UTRANUTRANUTRANUTRAN IuIuIuIu----CS Interface StackCS Interface StackCS Interface StackCS Interface Stack

Q.2150.1

Q.2630.1

RANAPIu User Plane

Protocol

TransportNetworkLayer

Physical Layer

TransportUser

NetworkPlane

Control Plane User Plane

TransportUser

NetworkPlane

Transport NetworkControl Plane

RadioNetworkLayer

ATM

SSCOP

AAL5

SSCOP

SSCF-NNI

AAL2AAL5

MTP3bMTP3b

SCCP

SSCF-NNI

MSC SGSN

SRNCDRNC

NBUE

RAN ApplicationPart is an evolutionof BSSMAP.- Multi-bearer

capability- New security features

Codec controlinformation (Codecs in CN)

One transport connection per Radio Access Bearer

SS7 Stack on SAAL-NNI

RANAPRANAPRANAPRANAP Functions Functions Functions Functions Radio Access Bearer (Radio Access Bearer (Radio Access Bearer (Radio Access Bearer (UEUEUEUE ---- CN bearer) handling (combined procedure):CN bearer) handling (combined procedure):CN bearer) handling (combined procedure):CN bearer) handling (combined procedure):• RAB Set-up (Including Queuing)• RAB Modification• Clearing (release) RAB (Including RAN initiated case)Iu ReleaseIu ReleaseIu ReleaseIu Release: Releases all Iu resources (Signaling link and U-Plane) related to the specified UE. Also includes RAN initiated caseRelocation:Relocation:Relocation:Relocation: Handling both SRNS Relocation (UE already in target RNC with Iur) and Hard Handover (simultaneous switch of Radio and Iu). Includes Loss-less relocation and Inter system HandoverPagingPagingPagingPaging: CN to page an UE for a terminating call/connectionCommon IDCommon IDCommon IDCommon ID: UE NAS Id sent to RNC for paging co-ordinationTrace InvocationTrace InvocationTrace InvocationTrace Invocation: CN may request UTRAN to start/stop tracing a specific UESecurity Mode Control:Security Mode Control:Security Mode Control:Security Mode Control: Controls Ciphering and Integrity CheckingLocation ReportingLocation ReportingLocation ReportingLocation Reporting: Requesting (CN) and reporting (RNC) UE locationData Volume ReportingData Volume ReportingData Volume ReportingData Volume Reporting: Requesting (CN) and reporting (RNC) Unsuccessfully transmitted DL dataInitial Initial Initial Initial UEUEUEUE MessageMessageMessageMessage: Carries the first Radio interface L3 message to the CN and sets up the Iu signalling connection. Direct TransferDirect TransferDirect TransferDirect Transfer: Carries CN and UE signalling information over Iu (content not interpreted by UTRAN)CN Information BroadcastCN Information BroadcastCN Information BroadcastCN Information Broadcast: This procedure allows the CN to set CN (NAS) related system information to be broadcast to all usersOverloadOverloadOverloadOverload: Used for flow control (to reduce flow) over the Iu interface e.g. due to processor overload at CN or UTRANReset:Reset:Reset:Reset: It is used to reset the CN or the UTRAN side of Iu interface in error situations (includes also resetting Signalling Connection)Error IndicationError IndicationError IndicationError Indication: Used for protocol errors where no other error applies


UTRANUTRANUTRANUTRAN IuIuIuIu----PS Interface StackPS Interface StackPS Interface StackPS Interface Stack MSC SGSN

SRNCDRNC

NBUE

SSCF-NNI

SSCOP

MTP3-B

AAL5

IP

SCTP

SCCP

M3UA

RANAPIu User Plane

Protocol


Physical Layer

TransportUser

NetworkPlane

Control Plane User Plane

TransportUser

NetworkPlane


RadioNetworkLayer

ATM

AAL5

IP

UDP

GTP-U

Physical Layer

ATM

No signalledtransport

connections(no AAL2

connection establishment

in TNL)

Same protocols as the Iu-CS Typically no

FP header (transparentmode)

Two options for signalling transport

User plane of theGPRS Tunnelling Protocol is used


UTRANUTRANUTRANUTRAN Iur Interface StackIur Interface StackIur Interface StackIur Interface Stack

AAL5

Q.2150.1

SSCF-NNI

SSCOP

MTP3-B

AAL5

IP

SCTP

SCCP

M3UA

SSCF-NNI

SSCOP

MTP3-B

IP

SCTP

M3UA

RNSAP

Control Plane User PlaneRadioNetworkLayer CCH

FPDCHFP


Physical Layer

TransportUser

NetworkPlane

TransportUser

NetworkPlane


ATM

Q.2630.1

AAL2

MSC SGSN

SRNCDRNC

NBUE

Dedicated and Common Channel Frame Protocol- Frame transfer- Synchronisation- Power control- ...

Composed by 3 modules: 1 Basic

mobility2 Dedicated

transport3 Common

transport

Each dedicated channel has a dedicated transport connection

Two options (IP and ATM based) for the signalling bearers

RNSAP RNSAP RNSAP RNSAP FunctionsFunctionsFunctionsFunctionsRadio Link ManagementRadio Link ManagementRadio Link ManagementRadio Link Management: This function allows the SRNC to manage radio links using dedicated resources in a DRNSPhysical Channel Reconfiguration:Physical Channel Reconfiguration:Physical Channel Reconfiguration:Physical Channel Reconfiguration: This function allows the DRNC to reallocate the physical channel resources for a Radio LinkRadio Link SupervisionRadio Link SupervisionRadio Link SupervisionRadio Link Supervision: This function allows the DRNC to report failures and restorations of a Radio LinkCompressed Mode Control [Compressed Mode Control [Compressed Mode Control [Compressed Mode Control [FDDFDDFDDFDD]:]:]:]: This function allows the SRNC to control the usage of compressed mode within a DRNSMeasurements on Dedicated Resources:Measurements on Dedicated Resources:Measurements on Dedicated Resources:Measurements on Dedicated Resources: This function allows the SRNC to initiate measurements on dedicated resources in the DRNS. The function also allows the DRNC to report the result of the measurementsDL Power Drifting Prevention [DL Power Drifting Prevention [DL Power Drifting Prevention [DL Power Drifting Prevention [FDDFDDFDDFDD]:]:]:]: This function allows the SRNC to adjust the DL power level of one or more Radio Links in order to avoid DL power drifting between the Radio LinksCCCHCCCHCCCHCCCH Signalling Transfer:Signalling Transfer:Signalling Transfer:Signalling Transfer: This function allows the SRNC and DRNC to pass information between the UE and the SRNC on a CCCH controlled by the DRNSPagingPagingPagingPaging: This function allows the SRNC to page a UE in a URA or a cell in the DRNSCommon Transport Channel Resources Management:Common Transport Channel Resources Management:Common Transport Channel Resources Management:Common Transport Channel Resources Management: This function allows the SRNC to utilise Common Transport Channel Resources within the DRNS (excluding DSCHresources for FDD)Relocation Execution:Relocation Execution:Relocation Execution:Relocation Execution: This function allows the SRNC to finalise (commit) a Relocation previously prepared via other interfacesReporting general error situationsReporting general error situationsReporting general error situationsReporting general error situations: This function allows reporting of general error situations, for which function specific error messages have not been defined


UTRANUTRANUTRANUTRAN Iub Interface StackIub Interface StackIub Interface StackIub Interface Stack

AAL5

Q.2150.2

SSCF-UNI

SSCOP

AAL5

SSCF-UNI

SSCOP

NBAP

Control Plane User PlaneRadioNetworkLayer CCH

FPDCHFP


Physical Layer

TransportUser

NetworkPlane

TransportUser

NetworkPlane


ATM

Q.2630.1

AAL2

MSC SGSN

SRNCDRNC

NBUE

Common NBAP to initialise UEcontext at the set-up of the first RL, and Logical O&M

Dedicated NBAP for UErelated signalling

Iub DCH FP is the same as Iur DCH FP (no user plane processing in DRNC, only MDC possible)

One signalling connection per traffic termination point in Node B. Simple SAAL-UNIstack

NBAP FunctionsNBAP FunctionsNBAP FunctionsNBAP FunctionsCell Configuration Management:Cell Configuration Management:Cell Configuration Management:Cell Configuration Management: This function gives the CRNC the possibility to manage the cell configuration information in a Node BCommon Transport Channel ManagementCommon Transport Channel ManagementCommon Transport Channel ManagementCommon Transport Channel Management: This function gives the CRNC the possibility to manage the configuration of Common Transport Channels in a Node BSystem Information Management:System Information Management:System Information Management:System Information Management: This function gives the CRNC the ability to manage the scheduling of System Information to be broadcast in a cellResource Event ManagementResource Event ManagementResource Event ManagementResource Event Management: This function gives the Node B the ability to inform the CRNC about the status of Node B resourcesConfiguration Alignment:Configuration Alignment:Configuration Alignment:Configuration Alignment: This function gives the CRNC and the Node B the possibility to verify that both nodes has the same information on the configuration of the radio resourcesMeasurements on Common Resources:Measurements on Common Resources:Measurements on Common Resources:Measurements on Common Resources: This function allows the CRNC to initiate measurements in the Node B. The function also allows the Node B to report the result of the measurements (e.g. Ptx/rx_Total)Synchronisation ManagementSynchronisation ManagementSynchronisation ManagementSynchronisation Management (TDD): This function allows the CRNC to manage the synchronisation of a TDD cell in a Node BRadio Link ManagementRadio Link ManagementRadio Link ManagementRadio Link Management: This function allows the CRNC to manage radio links using dedicated resources in a NodeBRadio Link SupervisionRadio Link SupervisionRadio Link SupervisionRadio Link Supervision: This function allows the CRNC to report failures and restorations of a Radio LinkMeasurements on Dedicated Resources:Measurements on Dedicated Resources:Measurements on Dedicated Resources:Measurements on Dedicated Resources: This function allows the CRNC to initiate measurements in the Node B. The function also allows the NodeB to report the result of the measurements (e.g. RL power)DL Power Drifting Correction (FDD)DL Power Drifting Correction (FDD)DL Power Drifting Correction (FDD)DL Power Drifting Correction (FDD): This function allows the CRNC to adjust the DL power level of one or more Radio Links in order to avoid DL power drifting between the Radio LinksReporting general error situations: Reporting general error situations: Reporting general error situations: Reporting general error situations: This function allows reporting of general error situations, for which function specific error messages have not been defined


CRNC Node B

RADIO LINK SETUP REQUEST

RADIO LINK SETUP RESPONSERadio LinkRadio LinkRadio LinkRadio Link

Parameter Description RL Information RL ID, C-ID, First RLS Indicator, Frame Offset, Chip Offset, Propagation Delay,

Diversity Control Field, DL Code Information, Initial DL transmission Power, Maximum DL power, Minimum DL power, SSDT Cell Identity, Transmit Diversity Indicator, Transmission Gap Pattern Sequence Information, Active Pattern Sequence Information

BTS id Identifier of the base station end of the radio link DCHs information For each DCH: UL TFS, DL TFS, CRC presence, etc… DSCH Information DSCH ID, Transport Format Set, Allocation/Retention Priority, Frame Handling

Priority DL Channelisation code number DL Channelization code DL Scrambling code DL Scrambling code (Shall be cell based) Min UL/DL Channelisation Code length Identifiers of the spreading codes to be used in the uplink/ downlink UL/DL TFCS UL/DL DPCH Transport Format Combination Set DL TPC DL Power Step Size DL TPC power step size for inner loop PC UL DPCCH and DL DPCH slot formats Slots format to be used Power Offset Information PO1, PO2 and PO3, DL DPCCH offsets (TFCI, TPC, Pilots) with respect to DPDCH

symbols UL SIR Target UL initial SIR Target in the WCDMA BTS PDSCH information PDSCH RL ID and code mapping Limited Power Increase Parameters for downlink limited power increase algorithm Uplink puncture Limit Limit used by the UE Max Number of UL DPDCHs Uplink multicode transmission information Uplink scrambling code Identifier of the long code to be used in uplink transmission.

Same code will probably be used for all the radio links of one terminal

Def: LDef: LDef: LDef: Logicalogicalogicalogical association between single E and a singleassociation between single E and a singleassociation between single E and a singleassociation between single E and a single UTRANUTRANUTRANUTRAN access pointaccess pointaccess pointaccess point

Radio linkRadio linkRadio linkRadio link: : : : A "radio link" is a logical association between single User Equipment and a single UTRAN access point. Its physical realization comprises one or more radio bearer transmissions. An UE can have more than one RL (softer or soft HO). Each RL is comprised of all the channel codes (DPDCH's) that are associated with the same physical layer control channel (DPCCH).

Radio Link modification: Radio Link modification: Radio Link modification: Radio Link modification: actions which effect the RL bit rate or bit rates of its RABs, as well as the RAB additions and releases


Access StratumAccess StratumAccess StratumAccess Stratum

Non

Non

Non

Non -- -- Access S

tratumAccess S

tratumAccess S

tratumAccess S

tratum

Access link betweenAccess link betweenAccess link betweenAccess link between UEUEUEUE and CNand CNand CNand CN

ACCESS LINKACCESS LINKACCESS LINKACCESS LINKACCESS LINKACCESS LINKACCESS LINKACCESS LINK

: SAP

UEUEUEUE UTRANUTRANUTRANUTRAN CNCNCNCN

UuUuUuUu IuIuIuIu

Radio Bearer serviceRadio Bearer serviceRadio Bearer serviceRadio Bearer service Iu bearer serviceIu bearer serviceIu bearer serviceIu bearer service

Radio Access BearersRadio Access BearersRadio Access BearersRadio Access Bearers

Signalling connectionSignalling connectionSignalling connectionSignalling connection

RRCRRCRRCRRC connectionconnectionconnectionconnection Iu connectionIu connectionIu connectionIu connection

Radio protocolsRadio protocolsRadio protocolsRadio protocols Iu protocolsIu protocolsIu protocolsIu protocols

Services and control protocols (CC, MM, SM,Services and control protocols (CC, MM, SM,Services and control protocols (CC, MM, SM,Services and control protocols (CC, MM, SM, GMMGMMGMMGMM))))

NonNonNonNon----Access StratumAccess StratumAccess StratumAccess Stratum, contains CN related signaling and services.

The Access StratumThe Access StratumThe Access StratumThe Access Stratum, handles all access dependent issues, and offers services to the Non-Access Stratum over Service Access Points (SAP) in the UE and the CN. It provides the Access Link Access Link Access Link Access Link between UE and CN.The Access Link consists of:• One or more independent and simultaneous UE-CN Radio Access Bearer Radio Access Bearer Radio Access Bearer Radio Access Bearer connectionsconnectionsconnectionsconnections, and• AAAA SignalingSignalingSignalingSignaling ConnectionConnectionConnectionConnection between the upper layer entities [CM/SM, CS/PS MM] ofUE and CN. The Signaling connection is comprised of two parts: RRCRRCRRCRRC connection connection connection connection (signalling connection)(signalling connection)(signalling connection)(signalling connection); and ; and ; and ; and Iu connection (expands theIu connection (expands theIu connection (expands theIu connection (expands the RRC RRC RRC RRC connection the connection the connection the connection the terminates interminates interminates interminates in UTRANUTRANUTRANUTRAN to CN)to CN)to CN)to CN)

The protocols over UuUuUuUu and IuIuIuIu interfaces are divided into two planes:•User plane protocolsUser plane protocolsUser plane protocolsUser plane protocols, that are implementing the actual radio access bearer service, carrying user data through the access stratum.•Control plane protocolsControl plane protocolsControl plane protocolsControl plane protocols, that are controlling the radio access bearers and the connection between UE and the network.


Radio Interface ProtocolsRadio Interface ProtocolsRadio Interface ProtocolsRadio Interface Protocols

L3L3L3L3

CCCC----plane signallingplane signallingplane signallingplane signalling UUUU----plane informationplane informationplane informationplane information

PHYPHYPHYPHY

L2/MACL2/MACL2/MACL2/MAC

L1L1L1L1

L2/L2/L2/L2/RLCRLCRLCRLC

MACMACMACMAC

LogicalLogicalLogicalLogical CHannelsCHannelsCHannelsCHannels, , , , MAC provides logical channels for data transfer services to the layers above MAC

L2/L2/L2/L2/BMCBMCBMCBMC

PDCPPDCP L2/L2/L2/L2/PDCPPDCPPDCPPDCP

The radio interface protocols are needed to set up, reconfigure and release the Radio Bearer services

TTTTransport CHannelransport CHannelransport CHannelransport CHannel bit ratebit ratebit ratebit rateuser bit rate added by the L2 header bit rate

RLCRLCRLCRLC RLCRLCRLCRLCRLCRLCRLCRLC

RLCRLCRLCRLCRLCRLCRLCRLC

RLCRLCRLCRLCRLCRLCRLCRLCRLCRLCRLCRLC

cont

rol

cont

rol

cont

rol

cont

rol

control

RRCRRCRRCRRC

BMC

RABsCC, MM, GMM, SM Higher L3Higher L3Higher L3Higher L3 sublayerssublayerssublayerssublayers/NAS/NAS/NAS/NAS

TransportTransportTransportTransport CHannelsCHannelsCHannelsCHannels, , , , information transfer service, which L1 offers to MAC and higher layers

The radio interface protocols are needed to set up, reconfigure and release the Radio Bearer services.

The radio interface consists of three protocol layers

• The physical layer (L1);

• The data link layer (L2); and

• The network layer (L3).

Layer 2 contains the following sub layers – Medium Access Control (MAC), Radio Link Control (RLC), Packet Data Convergence Protocol (PDCP) and Broadcast/Multicast Control (BMC). RLC is divided into Control (C) and User (U) planes, whilst PDCP and BMC exist only in the U-plane. Layer 3 consists of one protocol, denoted Radio Resource Control (RRC), which belongs to the C-plane.

Each block represents an instance of the corresponding protocol. The dashed lines represent the control interfaces through which the RRC protocol controls and configures the lower layers. The service access points between MAC and physical layer and between RLC and MAC sub layers provide the transport channels (TrCHs) and the logical channels (LoCHs), respectively. The TrCHs are specified for data The TrCHs are specified for data The TrCHs are specified for data The TrCHs are specified for data transport between physical layer and Layer 2 peer entities, whertransport between physical layer and Layer 2 peer entities, whertransport between physical layer and Layer 2 peer entities, whertransport between physical layer and Layer 2 peer entities, whereas logical channels eas logical channels eas logical channels eas logical channels define the transfer of a specific type of information over the rdefine the transfer of a specific type of information over the rdefine the transfer of a specific type of information over the rdefine the transfer of a specific type of information over the radio interfaceadio interfaceadio interfaceadio interface.


CS side protocol stack (UP)CS side protocol stack (UP)CS side protocol stack (UP)CS side protocol stack (UP)

AAL2

PHY

ATM

PHY

ATM

AAL2

FP

PHY

AAL2

PHY

ATMLinkLayer

PHY

AAL2

PHY

ATM

WCDMAL1

FP

WCDMAL1

E.g.Vocoder

PHY

PSTN/N-ISDN

AIuIubUu

IWU

RNC

Node B

UE

E

Iu -CS UPIu -CS UP

E.g.Vocoder

LinkLayer

A/m-lawPCM,UDI,etc.

A/m-lawPCM,UDI,etc.

MSC

RLC-U

MAC

RLC-U

MAC

Transcoding functionTransparent mode

SDH/PDH

Medium Access Control protocol (MAC)Medium Access Control protocol (MAC)Medium Access Control protocol (MAC)Medium Access Control protocol (MAC)The MAC is responsible for mapping of LoCH(s) onto appropriate TrCH(s).MAC selects the appropriate TF within an assigned TFS for each active TrCH depending on source rate (efficient use of transport channels), given the TFCS assigned by RRC.Priority handling between data flows of one UE (selecting a TFC for which high priority data is mapped onto L1 with a "high bit rate" TF).Priority handling between UEs by means of dynamic scheduling (MAC realizes priority handling on common and shared transport channels).Identification of UEs on common transport channels (need for inband identification, the identification functionality is naturally also placed in MAC).Mux/demux of RLC PDUs into/from TBs delivered to/from the physical layer on CCHs (service (LoCHs) multiplexing for CCHs).Mux/demux of RLC PDUs into/from TBSs delivered to/from the physical layer on DCHs (service (LoCHs) multiplexing for DCHs).Traffic volume monitoring (measurement of traffic volume on logical channels and reporting to RRC, based on the reported traffic volume information, RRC performs transport channel switching decisions).Dynamic TrCH type switching (execution of the switching between common and dedicated transport channels).Ciphering (for transparent RLC mode).Access Service Class (ASC) selection for RACH transmission (i.e. RACH sub-channel groups may be divided between different ASCs in order to provide different priorities of RACH usage).


PS side protocol stack (UP)PS side protocol stack (UP)PS side protocol stack (UP)PS side protocol stack (UP)

IP

AAL5

PHY

UDP

LLC/SNAP

GTP-U

ATM

PHY

ATM

AAL2

FP

PDCP

UDP

IP

LinkLayer

PHY

GTP

IP

AAL5

PHY

UDP

LLC/SNAP

GTP-U

ATM

UDP

IP

LinkLayer

PHY

GTP

AAL2

PHY

ATM

WCDMAL1

FP

WCDMAL1

PDCP

E.g.IPv4, IPv6

PHY

E.g.IPv4, IPv6

GnIuIubUuGGSN

3G- SGSNRNC

Node B

UEGi

RLC-U

MAC

RLC-U

MAC

Segmentation & reassembling(UM/AM)

Header compression(no payload compression)

Header for packet directing(UP only - RANAP otherwise)

UP only

TF scheduling andLoCH multiplexing

Radio Link Control protocol (Radio Link Control protocol (Radio Link Control protocol (Radio Link Control protocol (RLCRLCRLCRLC))))Provides segmentation (payloads units, PU) and retransmission services for both user (Radio Bearer) and control data (Signalling Radio Bearer)Each RLC instance is configured by RRC to operate in one of the three modes:Transparent modeTransparent modeTransparent modeTransparent mode (TrTrTrTr), no protocol overhead is added to higher layer dataUnacknowledged ModeUnacknowledged ModeUnacknowledged ModeUnacknowledged Mode (UMUMUMUM), no retransmission protocol is in use and data delivery is not guaranteedAcknowledged ModeAcknowledged ModeAcknowledged ModeAcknowledged Mode (AMAMAMAM), AAAAutomatic RRRRepeat reQQQQuest (ARQARQARQARQ) mechanism is used for error correctionFor all RLC modes, the CRC error detection is performed on the physical layer and the results of the CRC is delivered to the RLC together with the actual data (provided that the RLC PDUs are mapped one-to-one onto the Transport Blocks)Flow controlProtocol error detection and recoveryCipheringEtc...Packet Data Convergence Protocol (PDCP)Packet Data Convergence Protocol (PDCP)Packet Data Convergence Protocol (PDCP)Packet Data Convergence Protocol (PDCP)Exists only in the user plane and only for services from the PS domainContain header compression/decompression methods, which are needed to get better spectral efficiency for service requiring IP packets to be transmitted over the radio interfaceEvery PDCP compression entity uses zero, one or several compression algorithms type with a set of configurable parametersSeveral PDCP entities may use the same algorithm typeThe algorithm type and their parameters are negotiated during the RRC RABestablishment or reconfiguration procedures and indicated to the PDCP through thePDCP control service AP


Signalling Bearer

Control planeControl planeControl planeControl plane

PHY

ATM

AAL2

FP

RRC

AAL2

PHY

ATM

WCDMAL1

FP

WCDMA

L1

RRC

I ubUu

RNCNode BUE

RLC-C

MAC

RLC-C

MAC

GMM / SM / SMS

RANAPRelay

SCCP

PHY

ATM

AAL5

3G SGSN

GMM / SM / SMS

Signalling Bearer

RANAP

SCCP

PHY

ATM

AAL5

I u(PS)

Radio Resource Control protocol (RRC)Radio Resource Control protocol (RRC)Radio Resource Control protocol (RRC)Radio Resource Control protocol (RRC)RRC messages carry all parameters required to set-up, modify and release layer 2 and layer 1 protocol entities. Also, RRC messages carry in their payload all higher layer signalling (MM, CM). The mobility of the user equipment in the connected mode is controlled by RRC signalling (measurements, handover, cell update, etc.). After power on, the UE stays in Idle ModeIdle ModeIdle ModeIdle Mode until it transmits a request to establish an RRC Connection. In Idle Mode the connection of the UE is closed on all layers of the Access Stratum; the UE is identified by NAS identities such as IMSIIMSIIMSIIMSI, TMSITMSITMSITMSI and PPPP----TMSITMSITMSITMSI (Packet- TMSI); UTRAN has no own information about the individual Idle Mode UEs, and it can only address e.g. all UEs in a cell or all UEs monitoring a paging occasion. The The The The UTRANUTRANUTRANUTRAN Connected Mode Connected Mode Connected Mode Connected Mode is entered when the RRC Connection is established. The UE is assigned a Radio Network Temporary Identity (Radio Network Temporary Identity (Radio Network Temporary Identity (Radio Network Temporary Identity (RNTIRNTIRNTIRNTI) ) ) ) to be used as UEidentity on common transport channels. The transition to the UTRAN Connected Mode from the Idle Mode can only be initiated by the UE by transmitting a request for an RRC Connection. The event is triggered either by a paging request from the network or by a request from upper layers in the UE. RRCRRCRRCRRC connection released procedure (connection released procedure (connection released procedure (connection released procedure (UTRANUTRANUTRANUTRAN →→→→ UEUEUEUE)))): the purpose of this procedure is to release the RRC connection including the signalling link and all RBs between the UE and the UTRAN. By doing so, all established signalling flows and signalling connections will be released.

Frame ProtocolFrame ProtocolFrame ProtocolFrame ProtocolThe FP protocol layer is an Iub/Iur user plane protocol on top of AAL2 which is used to transfer user data, plus the necessary control information, between the SRNC and BTS; the FP protocol is also used to support some simple procedures e.g. timing adjustment, OLPC, etc...Frame structure: PayloadPayloadPayloadPayload, contains the data (typically one or more MAC PDUs); Header/trailerHeader/trailerHeader/trailerHeader/trailer, contains control information used for example for synchronization, power control, etc…


RRCRRCRRCRRC States and State States and State States and State States and State TTTTransitionsransitionsransitionsransitions

GSM-UTRA Inter-system Handover

Establish RR Connection

Release RR Connection

Initiation of temporary block flow

Release of temporary block flow

Cell reselection

Establish RRCConnection

Release RRC

Connection

UTRA Connected Mode UTRA Connected Mode UTRA Connected Mode UTRA Connected Mode (Allowed transitions)(Allowed transitions)(Allowed transitions)(Allowed transitions)

Establish RRCConnection

Release RRCConnection

URAURAURAURA____PCHPCHPCHPCH CELLCELLCELLCELL_PCHPCHPCHPCH

CELL_CELL_CELL_CELL_DCHDCHDCHDCH CELL_CELL_CELL_CELL_FACHFACHFACHFACH

Only by PagingOnly by PagingOnly by PagingOnly by Paging

Idle ModeIdle ModeIdle ModeIdle Mode

Camping on aCamping on aCamping on aCamping on a UTRANUTRANUTRANUTRAN cellcellcellcellCamping on a GSM / GPRS cellCamping on a GSM / GPRS cellCamping on a GSM / GPRS cellCamping on a GSM / GPRS cell

GPRS Packet GPRS Packet GPRS Packet GPRS Packet Transfer ModeTransfer ModeTransfer ModeTransfer Mode

GSM GSM GSM GSM Connected Connected Connected Connected

ModeModeModeMode

GPRS Packet Idle ModeGPRS Packet Idle ModeGPRS Packet Idle ModeGPRS Packet Idle Mode

6

2

4

5

7

18

9

1011

3

12

13

1) Via explicit signalling when all dedicated channels have been released; 2) Via explicit signalling; 3) Via explicit signalling; 4) The RRC Connection mobility is handled by measurement reporting and soft/hard handover procedure; 5) Via explicit signalling when a dedicated physical channel is established; 6) Via explicit signalling when UTRAN orders the UE to move to CELL_PCH state; 7) Via explicit signalling whenUTRAN orders the UE to move to URA _PCH state; 8) The UE monitors the broadcast channel and its location is known on cell level; 9) By paging from UTRAN (PAGING TYPE1 message) or through any uplink access; 10) The UE may use Discontinuous Reception (DRX), monitors the broadcast channel and its mobility is performed through cell reselection procedures moving to Cell_FACH state; 11) By paging from UTRAN (PAGING TYPE1 message) or uplink access using RACH; 12) The UE may use Discontinuous Reception (DRX), monitors the broadcast channel and its mobility is performed throughURA reselection procedures moving to CELL_FACH state; 13) The connection of the UE is closed on all layers of the AS (the UE is identified by NAS identities such as IMSI, TMSI and P-TMSI)

RRCRRCRRCRRC statesstatesstatesstatesCell_Cell_Cell_Cell_DCHDCHDCHDCH; in this state the dedicated physical channel (DPCH), plus eventually the physical downlink shared channel (PDSCH), is allocated to the UE. Is entered from the idle mode or by establishing a dedicated transport channel (DCH) from Cell_FACHstate. In this state the UE performs measurements according to the RRC: MEASUREMENT CONTROL message. The transition from Cell_DCH to Cell_FACHcan occur either through the expiration of an inactivity timer or via explicit signalling.Cell_Cell_Cell_Cell_FACHFACHFACHFACH; in this state no DPCH is allocated to the UE, the random access transport channel (RACH) and the forward transport channel (FACH) are used instead, for transmitting signalling and small amount of user data. The UE listens to the BCH system information and moves to Cell_PCH sub-state via explicit signalling when the inactivity timer on FACH expires.Cell_Cell_Cell_Cell_PCHPCHPCHPCH; in this state the UE location is known by the SRNC on a cell level, but it can be reached only via a paging message. This state allows low battery consumption. The UE may use Discontinuous Reception (DRX), reads the BCH to acquire valid system information and moves to Cell_FACH if paged by the network or through any uplink access, e.g. initiated by the terminal for cell reselection (cell update procedure).URAURAURAURA____PCHPCHPCHPCH; this state is similar to Cell_PCH, except that the UE executes the cell update procedure only if the UTRAN Registration Area (URA) is changed. One cell can belong to one or several URAs in order to avoid ping-pong effects. When the number of cell updates exceeds a certain limit, the UE may be moved to URA_PCHstate via explicit signalling. The DCCH cannot be used in this state and any activity can be initiated by the network via a paging request on PCCH or through an uplink access by the terminal using RACH.


States of States of States of States of BBBBearer earer earer earer AAAAllocationsllocationsllocationsllocations

Only DCH allocation possible

Both RACH / FACHand DCH possible

Real time and non-realtime bearers

allocated

RRC connection(no bearers allocated)

First RT bearersetup

Last RT bearerreleased

Real time bearer(s)allocated

Non-real time bearer(s)allocated

Last NRT bearerreleased

Last NRT bearerreleased

Last RT bearerreleased

First NRT bearersetup

NRT bearersetup

RT bearersetup

RT or NRTbearer setup

RT bearersetup

NRT bearersetup

RRC connectionestablished

RRC connectionreleased

Radio Access Bearer (Radio Access Bearer (Radio Access Bearer (Radio Access Bearer (RABRABRABRAB)))): service provided by the Access Stratum to the Non-Access Stratum for transferring user data between UE and CN (a bearer is described by a set of parameters/attributes of particular traffic aspects or Quality of Service (QoS) aspects for an application/service)

Radio Bearer (Radio Bearer (Radio Bearer (Radio Bearer (RBRBRBRB)))): service provided by the access stratum that runs on top of layer 2 between UE and UTRAN


Logical channels (1/2)Logical channels (1/2)Logical channels (1/2)Logical channels (1/2)• Control ChannelsControl ChannelsControl ChannelsControl Channels

• Control channels are used for transfer of control plane information only

• Broadcast Control Channel (BCCH)• Paging Control Channel (PCCH)• Common Control Channel (CCCH)• Dedicated Control Channel (DCCH)

• Traffic ChannelsTraffic ChannelsTraffic ChannelsTraffic Channels• Traffic channels are used for transfer of user plane

information only • Dedicated Traffic Channel (DTCH)• Common Traffic Channel (CTCH)

The data transfer services of the MAC layer are provided on logical channels. The type of information transferred defines each logical channel type. The logical channels are divided into two groups – Control Channels and Traffic Channels. The control channels are used for transfer of control plane information and the traffic channels are used for the transfer of user plane information only.Control ChannelsControl ChannelsControl ChannelsControl ChannelsBroadcast Control Channel (Broadcast Control Channel (Broadcast Control Channel (Broadcast Control Channel (BCCHBCCHBCCHBCCH)))), for broadcasting system control information in the downlink.Paging Control Channel (Paging Control Channel (Paging Control Channel (Paging Control Channel (PCCHPCCHPCCHPCCH)))), for transferring paging information in the downlink (used when the network does not know the cell location of the UE, or, the UE is in cell-connected state).Common Control Channel (Common Control Channel (Common Control Channel (Common Control Channel (CCCHCCCHCCCHCCCH)))), for transmitting control information between the network and UEs in both directions (commonly used by UEs having no RRCconnection with the network and by UEs using common transport channels when accessing a new cell after cell reselection).Dedicated Control Channel (Dedicated Control Channel (Dedicated Control Channel (Dedicated Control Channel (DCCHDCCHDCCHDCCH)))). Point-to-point bi-directional channel for transmitting dedicated control information between the network and a UE (established through RRC connection set up procedure).Traffic ChannelsTraffic ChannelsTraffic ChannelsTraffic ChannelsDedicated Traffic Channel (Dedicated Traffic Channel (Dedicated Traffic Channel (Dedicated Traffic Channel (DTCHDTCHDTCHDTCH)))). Point-to-point channel, dedicated to one UE for the transfer of user information (a DTCH can exist in both uplink and downlink directions).Common Traffic Channel (CTCH)Common Traffic Channel (CTCH)Common Traffic Channel (CTCH)Common Traffic Channel (CTCH). Point-to-multipoint unidirectional channel for transfer of dedicated user information for all or a group of specified UEs.


Logical Channels (2/2)Logical Channels (2/2)Logical Channels (2/2)Logical Channels (2/2)

BCHBCHBCHBCH PCHPCHPCHPCH DSCHDSCHDSCHDSCHFACHFACHFACHFACHRACHRACHRACHRACH DCHDCHDCHDCH

BCCHBCCHBCCHBCCH CCCHCCCHCCCHCCCHPCCHPCCHPCCHPCCHLogical Logical Logical Logical ChannelsChannelsChannelsChannels MAC SAPsMAC SAPsMAC SAPsMAC SAPs

CPCHCPCHCPCHCPCH((((FDDFDDFDDFDD only)only)only)only)

CTCHCTCHCTCHCTCH

DCHDCHDCHDCH

CCCHCCCHCCCHCCCH DTCHDTCHDTCHDTCH////DCCHDCCHDCCHDCCH DTCHDTCHDTCHDTCH////DCCHDCCHDCCHDCCH

Transport Transport Transport Transport ChannelsChannelsChannelsChannels

UpLinkUpLinkUpLinkUpLink DownLinkDownLinkDownLinkDownLink

BCCHBCCHBCCHBCCH Broadcast Control ChannelBroadcast Control ChannelBroadcast Control ChannelBroadcast Control ChannelBCHBCHBCHBCH Broadcast ChannelBroadcast ChannelBroadcast ChannelBroadcast ChannelCCCHCCCHCCCHCCCH Common Control ChannelCommon Control ChannelCommon Control ChannelCommon Control ChannelCCHCCHCCHCCH Control ChannelControl ChannelControl ChannelControl ChannelCPCHCPCHCPCHCPCH Common Packet ChannelCommon Packet ChannelCommon Packet ChannelCommon Packet ChannelCTCHCTCHCTCHCTCH Common Traffic ChannelCommon Traffic ChannelCommon Traffic ChannelCommon Traffic ChannelDCCHDCCHDCCHDCCH Dedicated Control ChannelDedicated Control ChannelDedicated Control ChannelDedicated Control Channel

DCHDCHDCHDCH Dedicated ChannelDedicated ChannelDedicated ChannelDedicated ChannelDSCHDSCHDSCHDSCH Downlink Shared ChannelDownlink Shared ChannelDownlink Shared ChannelDownlink Shared ChannelDTCHDTCHDTCHDTCH Dedicated Traffic ChannelDedicated Traffic ChannelDedicated Traffic ChannelDedicated Traffic ChannelFACHFACHFACHFACH Forward Access ChannelForward Access ChannelForward Access ChannelForward Access ChannelPCCHPCCHPCCHPCCH Paging Control ChannelPaging Control ChannelPaging Control ChannelPaging Control ChannelPCH PCH PCH PCH Paging ChannelPaging ChannelPaging ChannelPaging ChannelRACHRACHRACHRACH Random Access ChannelRandom Access ChannelRandom Access ChannelRandom Access Channel


Transport Channels (1/3)Transport Channels (1/3)Transport Channels (1/3)Transport Channels (1/3)

Transport Block Transport Block Transport Block Transport Block

Transport Block Transport Block Transport Block Transport Block TFI TFI TFI TFI

TrCH 1TrCH 1TrCH 1TrCH 1

TFCI TFCI TFCI TFCI Coding & MultiplexingCoding & MultiplexingCoding & MultiplexingCoding & Multiplexing

PhysicalPhysicalPhysicalPhysicalControlControlControlControl CHannelCHannelCHannelCHannel

PhysicalPhysicalPhysicalPhysicalDataDataDataData CHannelsCHannelsCHannelsCHannels

Higher LayersHigher LayersHigher LayersHigher Layers

Physical LayerPhysical LayerPhysical LayerPhysical Layer

TFCITFCITFCITFCI Decoding Decoding Decoding Decoding DeDeDeDe----multiplexing & Decodingmultiplexing & Decodingmultiplexing & Decodingmultiplexing & Decoding

PhysicalPhysicalPhysicalPhysicalControlControlControlControl CHannelCHannelCHannelCHannel

PhysicalPhysicalPhysicalPhysicalDataDataDataData CHannelsCHannelsCHannelsCHannels

TB & Error Indication TB & Error Indication TB & Error Indication TB & Error Indication TFI TFI TFI TFI

TB & Error Indication TB & Error Indication TB & Error Indication TB & Error Indication Transport Block Transport Block Transport Block Transport Block

Transport Block Transport Block Transport Block Transport Block TFI TFI TFI TFI

TrCH 2TrCH 2TrCH 2TrCH 2

TB & Error Indication TB & Error Indication TB & Error Indication TB & Error Indication TFI TFI TFI TFI

TB & Error Indication TB & Error Indication TB & Error Indication TB & Error Indication

In UTRAN the data generated at higher layers is carried over the radio interface using transport channels mapped onto different physical channels. The physical layer has been designed to support variable bit rate transport channelsvariable bit rate transport channelsvariable bit rate transport channelsvariable bit rate transport channels, to offer bandwidth-on-demand services, and to be able to multiplex several services within the same RRCconnection. The single output data stream from the coding and multiplexing unit is denoted Coded Composite Transport Channel (CCTrCH)Coded Composite Transport Channel (CCTrCH)Coded Composite Transport Channel (CCTrCH)Coded Composite Transport Channel (CCTrCH). A CCTrCH is carried by one physical control channel and one or more physical data channels. In general there can be more than one CCTrCH, but only one physical control channel is transmitted on a given connection.In 3GPP all TrCHs are defined as unidirectionalTrCHs are defined as unidirectionalTrCHs are defined as unidirectionalTrCHs are defined as unidirectional, i.e. uplink, downlink, or relay-link. Depending on services and state, the UE can have simultaneously one or several TrCHs in the downlink, and one or more TrCHs in the uplink. For each TrCH, at any Transmission Time Interval (Transmission Time Interval (Transmission Time Interval (Transmission Time Interval (TTITTITTITTI)))) the physical layer receives from upper layers a set of Transport Blocks and the corresponding Transport Format Transport Format Transport Format Transport Format Indicator (Indicator (Indicator (Indicator (TFITFITFITFI)))). Then Layer 1 combines the TFI information received from different TrCHs to the Transport Formant Combination Indicator (Transport Formant Combination Indicator (Transport Formant Combination Indicator (Transport Formant Combination Indicator (TFCITFCITFCITFCI)))). The TFCI is transmitted in the physical control channel to inform the receiver about what TrCHs are active in the current radio frame. In the downlink, in case of limited TFCSs the TFCI signalling may be omitted and Blind Transport Format Detection (Blind Transport Format Detection (Blind Transport Format Detection (Blind Transport Format Detection (BTFDBTFDBTFDBTFD)))) can be employed, where the TrCHs decoding can be done verifying in which position of the output block is matched with the CRC results.


Transport Channels (2/3)Transport Channels (2/3)Transport Channels (2/3)Transport Channels (2/3)• Common Common Common Common cccchannelshannelshannelshannels

• Resource divided between all or a group of users in a cell• Broadcast Channel (BCH)• Forward Access Channel (FACH)• Paging Channel (PCH)• Random Access Channel (RACH)• Uplink Common Packet Channel (CPCH)• Downlink Shared Channel (DSCH)

• Dedicated channelDedicated channelDedicated channelDedicated channel• Resource reserved for a single user• Dedicated Transport Channels (DCH)

Dedicated transport channels Dedicated transport channels Dedicated transport channels Dedicated transport channels The only dedicated transport channel specified in 3GPP is the DDDDedicated edicated edicated edicated CCCChannelhannelhannelhannel ((((DCHDCHDCHDCH)))), which support variable bit rate and services multiplexing. It is reserved for a single user. It carriers all user information coming from higher layers, including data for the actual service (speech frames, data, etc.) and control information (measurement control commands, UE measurement reports, etc.). It is mapped on the Dedicated Physical Data Channel (DPDCH). The DPCH is characterized by inner loop PC and fast data rate change on a frame-by-frame basis; it can be transmitted to part of the cell and supports soft/softer handover.Common transport channelsCommon transport channelsCommon transport channelsCommon transport channelsThe common transport channels are resource divided between all or a group of user in a cell (an in band identifier is needed). They do not support soft/softer HO, but some of them can have fast PC, e.g. Common Packet Channel (CCPCH) and slow PC, e.g. Downlink Shared Channel (DSCH), Forward Access Channel (FACH)Broadcast Channel (BCH)Broadcast Channel (BCH)Broadcast Channel (BCH)Broadcast Channel (BCH), it is used to transmit information (e.g. random access codes, cell access slots, cell type transmit diversity methods, etc.) specific to the UTRA network or to a given cell; is mapped onto the Primary Common Control Physical Channel (P-CCPCH), which is a downlink data channel, only.Forward Access Channel (FACH)Forward Access Channel (FACH)Forward Access Channel (FACH)Forward Access Channel (FACH), it carries downlink control information to terminals known to be located in the given cell. It is further used to transmit a small amount of downlink packet data. There can be more than one FACH in a cell, even multiplexed onto the same Secondary Common Control Physical Channel (S-CCPCH). The S-CCPCH may use different offsets between the control and data field at different symbol rate and may support slow PC.Paging Channel (PCH)Paging Channel (PCH)Paging Channel (PCH)Paging Channel (PCH), it carries data relevant to the paging procedure. The paging message can be transmitted in a single or several cells, according to the system configuration. It is mapped onto the S-CCPCH.Random Access Channel (RACH)Random Access Channel (RACH)Random Access Channel (RACH)Random Access Channel (RACH), it carries uplink control information, such as a request to set up an RRC connection. It is further used to send small amounts of uplink packet data. It is mapped onto the Physical Random Access Channel (PRACH).Uplink Common Packet Channel (CPCH)Uplink Common Packet Channel (CPCH)Uplink Common Packet Channel (CPCH)Uplink Common Packet Channel (CPCH), it carries uplink packet-based user data. It supports uplink inner loop PC, with the aid of a downlink Dedicated Physical Control Channel (DPCCH). Its transmission may span over several radio frames and it is mapped onto the Physical Common Packet Channel (PCPCH).Downlink Shared Channel (DSCH)Downlink Shared Channel (DSCH)Downlink Shared Channel (DSCH)Downlink Shared Channel (DSCH), it carries dedicated user data and/or control information and it can be shared in time between several users. It is as a pure data channel always associated with a downlink DCH. It supports the use of downlink inner loop PC, based on the associated uplink DPCCH. It is mapped onto the Physical Downlink Shared Channel (PDSCH).The common transport channels needed for the basic cell operation are RACH, FACH and PCH, while the use of the DSCH and CPCH may or may not be used by the operator.


Transport Channels (3/3)Transport Channels (3/3)Transport Channels (3/3)Transport Channels (3/3)

DPDCHDPDCHDPDCHDPDCH (Dedicated Physical Data Channel)

DPCCHDPCCHDPCCHDPCCH (Dedicated Physical Control Channel)

PRACHPRACHPRACHPRACH (Physical Random Access Channel)

PCPCHPCPCHPCPCHPCPCH (Physical Common Packet Channel)

CPICHCPICHCPICHCPICH (Common Pilot Channel)

PPPP----CCPCHCCPCHCCPCHCCPCH (Primary Common Control Physical Channel)

SSSS----CCPCHCCPCHCCPCHCCPCH (Secondary Common Control Physical Channel)

SCHSCHSCHSCH (Synchronisation Channel)

PDSCHPDSCHPDSCHPDSCH (Physical Downlink Shared Channel)

AICHAICHAICHAICH (Acquisition Indication Channel)

PICHPICHPICHPICH (Page Indication Channel)

DCHDCHDCHDCH

RACHRACHRACHRACH

CPCHCPCHCPCHCPCH

BCHBCHBCHBCH

FACHFACHFACHFACH

PCHPCHPCHPCH

DSCHDSCHDSCHDSCH

Mapping of transport channels onto physical channels

One UE can transmit only one CCTrCH at once, but multiple CCTrCHs can be simultaneously received in the forward (downlink) direction. In the uplink one TFCIrepresents the current TFs of all DCHs of the CCTrCH. RACHs are always mapped one-to-one onto physical channels (PRACHs), i.e. there is no physical layer multiplexing of RACHs. Further, only a single CPCH of a CPCH set is mapped onto aPCPCH, which employs a subset of the TFCs derived by the TFS of the CPCH set. ACPCH set is characterized by a set-specific scrambling code for access preamble and collision detection, and it is assigned to the terminal when a service is configured for CPCH transmission.

In the downlink the mapping between DCHs and physical channel data streams works in the same way as in the reverse direction. The current configuration of the coding and multiplexing unit is either signalled (TFCI) to the terminal, or optionally blindly (Blind TF Detection - BTFD) detected. Each CCTrCH has only zero or one corresponding TFCI mapped (each 10 ms radio frame) on the same DPCCH used in the connection. When the DSCH is employed in the communication, the DSCH TFIalso indicates the channelisation code used for the shared channel. A PCH and one or several FACH can be encoded and multiplexed together forming a CCTrCH, oneTFCI indicates the TFs used on each FACH and PCH carried by the same S-CCPCH. The PCH is always associated with the Paging Indicator Channel (PICH), which is used to trigger off the UE reception of S-CCPCH where the PCH is mapped. A FACHor a PCH can also be individually mapped onto a separate physical channel. The BCH is always mapped onto the P-CCPCH, without any multiplexing with other transport channels.


Formats and Configurations (1/2)Formats and Configurations (1/2)Formats and Configurations (1/2)Formats and Configurations (1/2)

TransportBlock Set(TBS) DCH2

T T I

T B

DCH1T T I

T B T BT B

Transport Block

Transport Block

Transport Block

T B

T B

Transmission Time Interval

T T I

T T I

T T I

Transport Format(TF)

Transport Format Set(TFS)

Transport Format Combination(TFC)

Transport Format Combination Set(TFCS)

Transport Format:Transport Format:Transport Format:Transport Format:• One DDDDynamic ynamic ynamic ynamic PPPPartartartart (Transport Block Size, Transport Block Set Size); and • One SSSSemiemiemiemi----SSSStatic tatic tatic tatic PPPPartartartart (TTI, type of EP [turbo code, convolutional code or no channel coding], coding rate, static RM parameter, size of CRC)

Transport Block (TB)Transport Block (TB)Transport Block (TB)Transport Block (TB), it is the basic unit exchanged between L1 and MAC for L1 processing; a TB typically corresponds to an RLC PDU or corresponding unit; layer 1 adds a CRC to each TB.Transport Block Set (TBS)Transport Block Set (TBS)Transport Block Set (TBS)Transport Block Set (TBS), it is defined as a set of TBs, which are exchanged between L1 and MAC at the same time instance using the same transport channel. Transport Block SizeTransport Block SizeTransport Block SizeTransport Block Size, it is defined as the number of bits in a TB; the Transport Block Size is always fixed within a given TBS, i.e. all TBs within a TBS are equally sized.Transport Block Set SizeTransport Block Set SizeTransport Block Set SizeTransport Block Set Size, it is defined as the number of bits in a TBS.Transmission Time Interval (Transmission Time Interval (Transmission Time Interval (Transmission Time Interval (TTITTITTITTI)))), it is defined as the inter-arrival time of TBSs, and is equal to the periodicity at which a TBS is transferred by the physical layer on the radio interface. It is always a multiple of the minimum interleaving period (i.e. 10 ms, the length of one Radio Frame). MAC delivers one TBS to the physical layer everyTTI.TTTTransportransportransportransport Format (Format (Format (Format (TFTFTFTF)))), it is the format offered by L1 to MAC (and vice versa) for thedelivery of a TBS during a TTI on a given TrCH. It consists of – one dynamic partdynamic partdynamic partdynamic part(Transport Block Size, Transport Block Set Size); and one semisemisemisemi----static partstatic partstatic partstatic part (TTI, type of error protection [turbo code, convolutional code or no channel coding], coding rate, static RM parameter, size of CRC).Transport Format Set (TFS)Transport Format Set (TFS)Transport Format Set (TFS)Transport Format Set (TFS), it is a set of TFs associated to a TrCH. The semi-static parts of all TFs are the same within a TFS. TB size, TBS size and TTI define the TrCH bit rate before L1 processing. Depending on the type of service carried by the TrCH, the variable bit rate may be achieved by changing between TTIs either the TBS Size only, or both the TBS and TBS Size.Transport Format Combination (TFC)Transport Format Combination (TFC)Transport Format Combination (TFC)Transport Format Combination (TFC), is an authorised combination of the currently valid TFs that can be simultaneously submitted to layer 1 on a CCTrCH of a UE, i.e. containing one TF from each TrCH being a part of the combination.


Formats and configurations (2/2)Formats and configurations (2/2)Formats and configurations (2/2)Formats and configurations (2/2)

TrCH1TrCH1TrCH1TrCH1 TrCH2TrCH2TrCH2TrCH2 TrCHnTrCHnTrCHnTrCHn

TransportTransportTransportTransportform

at setform

at setform

at setform

at set

Transport FormatTransport FormatTransport FormatTransport FormatCombination xCombination xCombination xCombination xTransport FormatTransport FormatTransport FormatTransport FormatCombination x+1Combination x+1Combination x+1Combination x+1

TransportTransportTransportTransportFormatFormatFormatFormat

• Relations of transport format, transport format set and Relations of transport format, transport format set and Relations of transport format, transport format set and Relations of transport format, transport format set and transport format combinationtransport format combinationtransport format combinationtransport format combination

Note: 1 RAB can have more than 1 TrCH, e.g. 144 kbps � 2x64kbps DCHsThe TFCS may be produced as a Cartesian product between TFSs of the TrCHs that are multiplexed onto a CCTrCH, each one of those considered as a vector. In theory every TrCH can have any TF in the TFC, but in practise only a limited number of possible combinations are selected.Transport Format Combination Set (TFCS)Transport Format Combination Set (TFCS)Transport Format Combination Set (TFCS)Transport Format Combination Set (TFCS), it is defined as a set of TFCs on a CCTrCH and a proprietary algorithm in the RNC produces it. The TFCS is what is given to MAC by L3 for control. When mapping data onto L1, MAC chooses between the different TFCs specified in the TFCS. MAC has any and only control over the dynamic-part of the TFC, since the semi-static part corresponds to the service attributes (quality, transfer delay) set by the admission control in the RNC. The selection of TFCs can be seen as the fast part of the radio resource control dedicated to MAC, close to L1. Thereby the bit rate can be changed very fast, without any need of L3 signalling. Transport Format Indicator (Transport Format Indicator (Transport Format Indicator (Transport Format Indicator (TFITFITFITFI)))), as pointed out in the introduction, it is a label for a specific TF within a TFS. It is used in the inter-layer communication between MAC and L1, each time a TBS is exchanged between the two layers on a transport channel.Transport Format Combination Indicator (TFCI)Transport Format Combination Indicator (TFCI)Transport Format Combination Indicator (TFCI)Transport Format Combination Indicator (TFCI), as explained alredy, it is used in order to inform the receiving side of the currently valid TFC, and hence to decode, de-multiplex and transfer the received data to MAC on the appropriate TrCHs. MAC indicates the TFI to L1 at each delivery of TBSs on each TrCH. L1 then builds the TFCI from the TFIs of all parallel TrCHs of the UE, processes the TBs and appropriately appends the TFCI to the physical control signalling (DPCCH). Through the detection of the TFCI the receiving side is able to identify the TFC.


Function of the Physical LayerFunction of the Physical LayerFunction of the Physical LayerFunction of the Physical Layer• FEC encoding/decoding of transport channels, measurements

and indication to higher layers (e.g. BER, SIR, interference power, transmission power, etc.)

• Macro diversity distribution/combining and softer handover execution

• Error detection on transport channels (CRC)• Multiplexing of transport channels and de-multiplexing of

CCTrCHs, rate matching, mapping of CCTrCHs on physical channels

• Modulation/demodulation and spreading/despreading of physical channels, frequency and time (chip, bit, slot, frame) synchronisation, closed-loop power control (inner loop PC), power weighting, combining of physical channels

• RF processing

See references for more information.


Uplink TrCH MultiplexingUplink TrCH MultiplexingUplink TrCH MultiplexingUplink TrCH Multiplexing

Rat

em

atch

ing

Phys

ical

cha

nnel

segm

enta

tion

Rad

io fr

ame

segm

enta

tion

2nd

inte

rleav

ing

/RF

Phys

ical

cha

nnel

map

ping

Cha

nnel

cod

ing

Rat

e m

atch

ing

TrBk

conc

aten

atio

n /

Cod

e bl

ock

segm

enta

tion

CR

C a

ttach

men

t / T

B

Rad

io fr

ame

equa

lisat

ion

inte

rleav

ing

/TTI

TrC

H M

ultip

lexi

ng

CC

TrC

HC

CTr

CH

CC

TrC

HC

CTr

CH

PhCHPhCHPhCHPhCH #1#1#1#1


TrC

H #

1Tr

CH

#1

TrC

H #

1Tr

CH

#1

MAC and MAC and MAC and MAC and higher layershigher layershigher layershigher layers

Spreading/ScramblingSpreading/ScramblingSpreading/ScramblingSpreading/Scramblingand Modulationand Modulationand Modulationand Modulation

NoNoNoNo DTXDTXDTXDTX but dynamic rate matchingbut dynamic rate matchingbut dynamic rate matchingbut dynamic rate matchingfor Variable Rate Handling (SF) after Muxfor Variable Rate Handling (SF) after Muxfor Variable Rate Handling (SF) after Muxfor Variable Rate Handling (SF) after Mux

Puncturing or better repetitionPuncturing or better repetitionPuncturing or better repetitionPuncturing or better repetition

Data arrives to the coding/multiplexing unit in form of transport block sets once every Transmission Time Interval. The transmission time interval is transport-channel specific from the set {10 ms, 20 ms, 40 ms, 80 ms}.Error detectionError detectionError detectionError detection is provided on transport blocks through a Cyclic Redundancy Check. The CRC length is determined by the admission control in the RNC and can be 24, 16, 12, 8 or 0 bits; the more bits the CRC contains, the lower is the probability of having undetected errors in the receiver. The CRC is carried out based on the CRC parity bits of each transport block. Regardless of the result of the CRC check, all TBs are delivered to L2 along with the associated error indications. This estimation is then used as quality information for uplink macro diversity selection/combining in the RNC. Also, this indication may be directly used as an error indication to L2 for each erroneous TB in TM, UM and AM RLC, provided that RLC PDUs are one-to-one mapped onto TBs.Depending on whether the TB fits in the available code block size (channel coding method), the transport blocks in a TTI are either concatenated or segmentedconcatenated or segmentedconcatenated or segmentedconcatenated or segmented to coding blocks of suitable size. The benefit of the concatenation is better performance in terms of lower overhead due to encoder tail bits and in some cases due to better channel coding performance because of the larger block size.Channel codingChannel codingChannel codingChannel coding and radio frame equalisationradio frame equalisationradio frame equalisationradio frame equalisation is performed on the coding blocks after the concatenation or segmentation operation. The convolutional coding is supposed to be used with relative low data rate, e.g. the BTFD using Viterbi decoder is much faster than turbo coding. Whereas turbo coding is applied for higher data rates and brings performance benefits when large enough block size are achieved for significant interleaving effect. As an example, the AMR speech serviceAMR speech serviceAMR speech serviceAMR speech service (coordinated TrCHscoordinated TrCHscoordinated TrCHscoordinated TrCHs, multiplexed in the FP) uses UEP (Unequal Error Protection): Class AClass AClass AClass A bits, strong protection (1/3 cc and 12 bit CRC); Class BClass BClass BClass B bits, less protected (1/3 cc); and Class CClass CClass CClass Cbits, the least protected (1/2 cc). The function of the radio frame equalisation (padding)radio frame equalisation (padding)radio frame equalisation (padding)radio frame equalisation (padding) is to ensure that data arrive after channel coding can be divided into equalised blocks when transmitted over more than a single 10 ms radio frame. The radio frame size equalisation is only performed in the UL, because in the DL the rate matching output block length is already produced in blocks of equal size per frame.


Downlink TrCH MultiplexingDownlink TrCH MultiplexingDownlink TrCH MultiplexingDownlink TrCH Multiplexing

Phys

ical

cha

nnel

segm

enta

tion

Rad

io fr

ame

segm

enta

tion

2nd

inte

rleav

ing/

RF

Phys

ical

cha

nnel

map

ping

Cha

nnel

cod

ing

Rat

em

atch

ing

Rat

e m

atch

ing

TrBk

conc

aten

atio

n /

Cod

e bl

ock

segm

enta

tion

CR

C a

ttach

men

t / T

B

1st i

nser

tion

ofD

TXin

dica

tion

1st

inte

rleav

ing/

TTI

TrC

H M

ultip

lexi

ng

CC

TrC

HC

CTr

CH

CC

TrC

HC

CTr

CH



TrC

H #

1Tr

CH

#1

TrC

H #

1Tr

CH

#1

2nd

inse

rtion

ofD

TXin

dica

tion

MAC and MAC and MAC and MAC and higher layershigher layershigher layershigher layers

Spreading/ScramblingSpreading/ScramblingSpreading/ScramblingSpreading/Scramblingand Modulationand Modulationand Modulationand Modulation

DTXDTXDTXDTX for Variable Rate Handling after Muxfor Variable Rate Handling after Muxfor Variable Rate Handling after Muxfor Variable Rate Handling after Mux

Puncturing or better repetitionPuncturing or better repetitionPuncturing or better repetitionPuncturing or better repetitionStatic Rate Matching (EStatic Rate Matching (EStatic Rate Matching (EStatic Rate Matching (Ebbbb/N/N/N/N0000 balancing or Ebalancing or Ebalancing or Ebalancing or Essss/N/N/N/N0000 matching)matching)matching)matching)

The 1st interleaving (or radio1st interleaving (or radio1st interleaving (or radio1st interleaving (or radio----frame interleaving)frame interleaving)frame interleaving)frame interleaving) is used when the delay budget allows more than 10 ms of interleaving period. The 1st interleaving period is related to the TTIand can be 20, 40 or 80 ms. When different TrCHs are multiplexed together for a single connection, the positions where the corresponding TTIs start are time aligned. If the 1st interleaving is used, the frame segmentation will distribute the data coming from the 1st interleaving over 2, 4, or 8 consecutive frames in line with the interleaving length.Rate matchingRate matchingRate matchingRate matching is used for matching the number of bits to be transmitted to the number of bits available on a single frame (DPCH). This is achieved either by puncturing or by repetition. The amount of repetition/puncturing for each service depends on the service combination and their QoS requirements. In the uplink direction, repetition is preferred, puncturing is used to avoid multicode transmission or when facing the limitations of the terminal transmitter or base station receiver. The rate matching procedure takes into account the number of bits of all TrCHs active in that frame. The admission control in the RNC provides a semi static parameter, the rate-matching attribute, to control the relative rate matching between different TrCHs. The rate-matching attribute is used to calculate the rate matching value when multiplexing several TrCHs for the same frame. With the aid of the rate matching attribute and TFCI the receiver can calculate backwards the rate matching parameters used and perform the inverse operation. By adjusting the rate-matching attribute, admission control of the RNC fine-tunes the quality of different services in order to reach an equal or near equal symbol power level requirement for all services.The variable rate handling variable rate handling variable rate handling variable rate handling is performed after TrCH multiplexing for matching the total instantaneous rate of the multiplexed TrCHs to the channel bit rate of the DPDCH (when the transport block sets do not contain the maximum number of DPDCH bits). The number of bits on a TrCH can vary between different TTIs. In the downlink the transmission is interrupted if the number of bits is lower than maximum allowed by the DPDCH. In the uplink bits are repeated or punctured to ensure that the total bit rate after TrCHs multiplexing is identical to the total channel bit rate of the allocated DPCHs. The rate matching is performed in a more dynamic way and may vary on a frame-by-frame basis.


Channel CodingChannel CodingChannel CodingChannel Coding

Type of TrCH Coding scheme Coding rate BCH PCH

RACH 1/2

Convolutional coding

1/3, 1/2 Turbo coding 1/3 CPCH, DCH, DSCH, FACH

No coding

Note: only the channel coding schemes reported in the table can be applied to TrCHs, i.e. convolutional coding (CC), turbo coding or no coding (no limitation on the coding block size).

Ex. AMR speech serviceAMR speech serviceAMR speech serviceAMR speech service (coordinated TrCHs, multiplexed in the FP) uses UEP (Unequal Error Protection): Class AClass AClass AClass A bits, strong protection (1/3 cc and 12 bit CRC1/3 cc and 12 bit CRC1/3 cc and 12 bit CRC1/3 cc and 12 bit CRC); Class BClass BClass BClass B bits, less protected (1/3 cc1/3 cc1/3 cc1/3 cc); and Class CClass CClass CClass C bits, the least protected (1/2 cc1/2 cc1/2 cc1/2 cc).

The multicode transmissionmulticode transmissionmulticode transmissionmulticode transmission is employed when the total bit rate to be transmitted on a CCTrCH exceeds the maximum bit rate of the DPCH. The multicode transmission depends on the multicode capabilities of UE and Node B, and consists of several parallel DPDCHs transmitted for one CCTrCH using the same spreading factor. In the downlinkIn the downlinkIn the downlinkIn the downlink, if several CCTrCHs are employed for one UE, each CCTrCH can have a different spreading factor, but only one DPCCH is used for them in the connection. In the uplinkIn the uplinkIn the uplinkIn the uplink, the UE can use only one CCTrCH simultaneously. Multi-code operation is possible if the maximum allowed amount of puncturing has already been applied. For the different codes it is mandatory for the terminal to use the SF 4SF 4SF 4SF 4. Up to 6 parallel DPDCHs and only one DPCCH per connection can be transmitted.

The second interleavingsecond interleavingsecond interleavingsecond interleaving is also called intraintraintraintra----frame interleavingframe interleavingframe interleavingframe interleaving (10 ms radio frame interleaving). It consists of block inter-column permutations, separately applied for each physical channel (if more than a single code channel is transmitted). The amount of bits output at this stage is exactly the number of bits the spreading factor of that frame can transmit.


Example of DCH Bit Rate CalculationExample of DCH Bit Rate CalculationExample of DCH Bit Rate CalculationExample of DCH Bit Rate Calculation

• Assume a TB size of 336 bits (= 320 bit payload + 16RLC header), a TBS size = 2 TBs, and a TTI = 10 ms

• DCHDCHDCHDCH bit ratebit ratebit ratebit rate• 336*2/10 = 67.2 kbit/s

• DCHDCHDCHDCH user bit rateuser bit rateuser bit rateuser bit rate, which is defined as the DCH bit rate minus the RLC header rate, is given by • (336-16) *2/10 = 64 kbit/s.

• DPDCHDPDCHDPDCHDPDCH bit ratebit ratebit ratebit rate = (TB size + RLC header + CRC_bits + Tail_bits)*TBS size * [(1-Puncturing) or Repetitionrate]*Coding_Rate/TTI= DPCH bit rate – DPCCH overhead (downlink only)

Note: The DCH user bit rate is used for radio network planning.


Example for 3.4 kbps Example for 3.4 kbps Example for 3.4 kbps Example for 3.4 kbps DDDDataataataata (DCCH) (DCCH) (DCCH) (DCCH) ---- DLDLDLDL Transport blockCRC attachment

CRC

Convolutional coding R=1/3

Rate matching

148

148

516*B

Tail8*B

(516+NRM)*B

1st interleaving

16 bits

Radio frame segmentation

#1 [ (516+NRM)*B+NDI]/

4

To TrCh Multiplexing

(516+NRM)*B+NDI

#2 #4

Tail bit attachment

164*B

#3

TrBk concatination B TrBks (B =0,1)

164*B

(516+NRM)*B+NDI

Insertion of DTX indication*

[ (516+NRM)*B+NDI]/4

[ (516+NRM)*B+NDI]/4

[ (516+NRM)*B+NDI]/4

* Insertion of DTX indication is used only if the position of the TrCHs in the radio frame is fixed.

Transport block size 148 bits

Transport block set size 148*B bits (B=0, 1)

CRC 16 bits

Coding CC, coding rate = 1/3

TTI 40 ms = 4 R. Frames

DCH bit rateDCH bit rateDCH bit rateDCH bit rate= 148/40 = 3.7 kb/s (with RLC header)

DCH encoded bit rateDCH encoded bit rateDCH encoded bit rateDCH encoded bit rate= (148+16+8)*1*3*/40 = 12.9 kbps �

DL DPCH 15 ksps15 ksps15 ksps15 ksps (30 kb/s= SF 256SF 256SF 256SF 256) �

(516 + NNNNRMRMRMRM)/4 = 300 – DPCCH HH (30%)=

129+NNNNRMRMRMRM /4 = 210 (in a Radio Frame)

Hence, NNNNRMRMRMRM = (210-129) * 4 = 324324324324

� Repetition Repetition Repetition Repetition = 30*0.7 / 12.9 =1.63 = RMRMRMRM

DCH bit rateDCH bit rateDCH bit rateDCH bit rate= 148/40 = 3.7 kb/s (with RLC header)

DCH encoded bit rateDCH encoded bit rateDCH encoded bit rateDCH encoded bit rate= (148+16+8)*1*3*/40 = 12.9 kbps �

DL DPCH 15 ksps15 ksps15 ksps15 ksps (30 kb/s= SF 256SF 256SF 256SF 256) �

(516 + NNNNRMRMRMRM)/4 = 300 – DPCCH HH (30%)=

129+NNNNRMRMRMRM /4 = 210 (in a Radio Frame)

Hence, NNNNRMRMRMRM = (210-129) * 4 = 324324324324

� Repetition Repetition Repetition Repetition = 30*0.7 / 12.9 =1.63 = RMRMRMRM

Example for 3.4 kbps dataNOTE: This example can be applied to DCCH. In this example, it is assumed that maximum data rate of RLC payload is 3.4 kbps, and that MAC and RLC overhead in a transport block is 12 bits.


Example for StandExample for StandExample for StandExample for Stand----AAAAlone lone lone lone MMMMappingappingappingapping of 3.4 of 3.4 of 3.4 of 3.4 kbps kbps kbps kbps DDDDataataataata ---- DLDLDLDL

15 ksps DPCH

2nd interleaving

Physical channelmapping 1 2 15

CFN=4Nslot

Pilot symbol

TPC

1 2 15

CFN=4N+1slot

1 2 15

CFN=4N+2slot

1 2 15

CFN=4N+3slot

#1 #2 #3 #4

3.4 kbps data

129+NRM /4=150

150

129+NRM /4=150 129+NRM /4=150 129+NRM /4=150

150 150 150

Symbol rateSymbol rateSymbol rateSymbol rate(ksps)(ksps)(ksps)(ksps)

NNNNpilotpilotpilotpilot(bits/slot)(bits/slot)(bits/slot)(bits/slot)

NNNNTFCITFCITFCITFCI(bits/slot)(bits/slot)(bits/slot)(bits/slot)

NNNNTPCTPCTPCTPC(bits /slot(bits /slot(bits /slot(bits /slot)

NNNNdata1data1data1data1(bits /slot)(bits /slot)(bits /slot)(bits /slot)

NNNNdata2data2data2data2(bits /slot)(bits /slot)(bits /slot)(bits /slot)

15(SF = 256)

4 0 2 2 12

DPCCH overhead = (4+2)/20 = 30%30%30%30%DPCCH overhead = (4+2)/20 = 30%30%30%30%

Example for Stand-alone mapping of 3.4 kbps data on a 30 kbps (= 15 ksps)NOTE: This example can be applied to Stand-alone mapping of DCCH. The Table shows example of physical channel parameters for stand-alone mapping of 3.4 kbps data.


Example for 64/128/144 kbps packet dataExample for 64/128/144 kbps packet dataExample for 64/128/144 kbps packet dataExample for 64/128/144 kbps packet dataThe number of TrChs 1Transport block size 336 bits

Transport block Set size

64 kbps 336*B bits (B = 0, 1, 2, 3, 4)128 kbps 336*B bits (B = 0, 1, 2, 4, 8)144 kbps 336*B bits (B = 0, 1, 2, 4, 8, 9)

CRC 16 bitsCoding Turbo coding, coding rate = 1/3TTI 20 ms

Transport block

CRC attachment

CRC

Turbo coding R=1/3

Rate matching

336

336 16

352* B

TrBk concatenation

1056* B+12*�B/9�+NRM

1st interleaving

1056* B +12*�B/9�+NRM

1056*B Tail bit attachment

Tail12*�B/9�1056*B

To TrCh Multiplexing

B TrBks (B=0, 1, 2, 3, 4, 8, 9)

#1 (1056* B +12*�B/9�+NRM)/2

Radio frame segmentation

#2(1056* B +12*�B/9�+NRM)/2

Example for 64/128/144 kbps packet dataNOTE: In this example, it is assumed that maximum data rate of RLC payload is 64/128/144 kbps, and MAC and RLC overhead in a transport block is 16 bits.


Example for multiplexing of Example for multiplexing of Example for multiplexing of Example for multiplexing of 64/128/144/384 kbps and 3.4 kbps64/128/144/384 kbps and 3.4 kbps64/128/144/384 kbps and 3.4 kbps64/128/144/384 kbps and 3.4 kbps

#1

3.4 kbps data

#2 #3 #4

#1 #1

#1 #2 #1 #2

Packet data

1 2 15

CFN=4N slot

Pilot symbol TFCI&TPC

1 2 15

CFN=4N+1

1 2 15

CFN=4N+2

1 2 15

CFN=4N+3

TrCH multiplexing

Packet data

#2 #2 #1 #3 #2 #4

Insertion of DTX indication

2nd interleaving

Physical channel mapping

#1 #P #1 #P #1 #P #1 #P

Physical channel segmentation

#1 #P #1 #P #1 #P #1 #P

#1

#P

DPDCH

Data rate

(kbps)

Symbol rate

(ksps)

No.of physical channel: P

Npilot

(bits)

NTFCI

(bits)

NTPC

(bits)

Ndata1

(bits)

Ndata2

(bits)

64 120 1 8 8 4 28 112

128 240 1 16 8 8 56 232

144 240 1 16 8 8 56 232

240 3 16 8 8 56 232 384

480 1 16 8 8 120 488

Example for multiplexing of 64/128/144/384 kbps packet data and 3.4 kbps dataNOTE: This example can be applied to multiplexing 64/128/144/384 kbps packet data and DCCH. The table shows an example of physical channel parameters for multiplexing of 64/128/144/384 kbps packet data and 3.4 kbps data


Examples of Layer 3 ProceduresExamples of Layer 3 ProceduresExamples of Layer 3 ProceduresExamples of Layer 3 Procedures


MOCMOCMOCMOC (1/2)(1/2)(1/2)(1/2)RNC CNUE BTS

L1 synch

(CP) AAL5 ALCAP: AAL2 Connection Setup (CID1 for DCCH/DCH1)

UE-CN signalling (authentication, ciphering, etc…) = RRC connection + Iu connection

(CP-UE) RRC: CONNECTION REQUEST (CCCH/RACH/PRACH/FP/AAL2)

(CP) AAL5: C-NBAP: RADIO LINK SETUP

(CP) AAL5: C-NBAP: RL SETUP RESPONSE

(CP-UE) RRC: CONNECTION SETUP (S-CCPCH/FACH/CCCH/FP/AAL2)

(CP) AAL5: D-NBAP: SYNCH INDICATION

(CP-UE) RRC:CONNECTION SETUP COMPLETE (DCCH/DCH1/UL DPDCH/FP/AAL2)

(CP-UE) RRC:INITIAL DIRECT TRANSFER (DCCH/DCH1/UL DPDCH/FP/AAL2)(CP) AAL5: RANAP:INITIAL UE MESSAGE

AICH

PRACH: Preamble

UE Information ElementsInitial UE identityActivation timeNew U-RNTIUTRAN DRX cycle lengthcoefficientRe-establishment timerCapability update requirementRB Information ElementsSignalling RB information tosetup listSignalling RB information tosetupTrCH Information ElementsUplink transport channelsAdded or Reconfigured TrCH information listAdded or Reconfigured ULTrCH informationDownlink transport channelsAdded or Reconfigured TrCH information listAdded or Reconfigured DLTrCH informationPhyCH information elementsFrequency infoUplink radio resourcesMaximum allowed UL TXpowerUplink DPCH infoPRACH Info (for RACH)Downlink radio resourcesDownlink information foreach radio link


MOCMOCMOCMOC (2/2)(2/2)(2/2)(2/2)RNC CNUE BTS

AAL5 ALCAP: AAL2 Connection Setup (CID2 for DTCH/DCH2)

Connection established

(CP) AAL5: RANAP: COMMON ID

RANAP: RAB ASSIGNMENT REQUESTD-NBAP:RL RECONFIGURATION PREPARE

D-NBAP: RL RECONFIGURATION READY

AAL2 Connection Setup

NBAP: RL RECONFIGURATION COMMIT

(CP-UE) RRC:RADIO BEARER SETUP (AAL2/FP/DCCH/DCH1/DPCH)

(CP-UE) RRC:RADIO BEARER SETUP COMPLETE (DCCH/DCH1/DPDCH/FP/AAL2)RANAP:RAB ASSIGNMENT RESPONSE

DCHs to ModifyDCH ID

DCHs to AddDCH IDLimited Power IncreaseUL Transport Format SetDL Transport Format SetFrame Handling PriorityPayload CRC Presence indicatorUL FP ModeQE-SelectorToAWSToAWE

Radio Access Bearer service attributes -> AC


MTCMTCMTCMTC (1/2)(1/2)(1/2)(1/2)RNC CNUE BTS

RANAP:PAGING(CP-UE) RRC:PAGING TYPE 1 (FP/AAL2/PCCH/PCH/S-CCPCH)

RRC:RRC CONNECTION SETUP

(CP) AAL5 NBAP:SYNCH INDICATION

(CP) AAL5: NBAP:RADIO LINK SETUP

(CP) AAL5 NBAP: RL SETUP RESPONSE

RRC:CONNECTION SETUP COMPLETE

RRC:INITIAL DIRECT TRANSFER(CP) AAL5: RANAP:INITIAL UE MESSAGE

L1 synch

(CP) AAL5 ALCAP: AAL2 Connection Setup (CID1 for DCCH/DCH1)

UE-CN signalling (authentication, ciphering, etc…)- RRC connection + Iu connection

(CP-UE) RRC:RRC CONNECTION REQUEST (RACH/PRACH/FP/AAL2)

AICH

PRACH: Preamble

UE has no RRC connection.


MTCMTCMTCMTC (2/2)(2/2)(2/2)(2/2)RNC CNUE BTS

(CP) AAL5: RANAP: COMMON ID

AAL5 ALCAP: AAL2 Connection Setup (CID2 for DTCH/DCH2)

Connection established

RANAP: RAB ASSIGNMENT REQUESTNBAP:RL RECONFIGURATION PREPARE

NBAP: RL RECONFIGURATION READY

AAL2 Connection Setup

NBAP: RL RECONFIGURATION COMMIT

RRC:RADIO BEARER SETUP

RRC:RADIO BEARER SETUP COMPLETERANAP:RAB ASSIGNMENT RESPONSE


PagingPagingPagingPaging

UE Node B RNC CN

(CP) AAL5: RANAP:PAGING

UE has no RRC connection.

RRC connection establishment

Paging response

(CP-UE) RRC:PAGING TYPE 1 (FP/AAL2/PCCH/PCH/S-CCPCH)


From Cell_From Cell_From Cell_From Cell_FACHFACHFACHFACH to Cell_to Cell_to Cell_to Cell_DCHDCHDCHDCHBTS RNC-L2RNC-NBAP RNC-RRC RNC-RRM

UL & DL packet scheduling

UE IubUu

Radio link setup (NBAP) and AAL2 transmission setup

BTS providesperiodical cell load info to RRM

NBAP: RADIO RESOURCE INDICATIONRR_ind

PS indicates UE about the granted capacity

[FACH] RRC: RADIO BEARER RECONFIGURATIONCapacity_allocation

NRT RB establishment for UE

UE in CELL_FACH state

RNC has data to send in downlink : MAC requests DL

capacity from RRM

DL_capacity_req

Channel type selection -> DCH

[DCH] RRC: RADIO BEARER RECONFIGURATION COMPLETE L2 configuration

[RACH] RRC: MEASUREMENT REPORT

UL_capacity_req

UE has data to sendin uplink : RRC of UE requests

uplink capacity from RRM

Traffic volume measurement

triggers

L1: SYNC

NBAP: SYNCHRONIZATION INDICATIONSync_ind

RLC-PDU transportation on DCH

UE in CELL_DCH state


From Cell_From Cell_From Cell_From Cell_DCHDCHDCHDCH to Cell_to Cell_to Cell_to Cell_FACHFACHFACHFACH

BTS RNC-L2RNC-NBAP RNC-RRC RNC-RRM

Define inactivity timer

L2 configuration

[RACH] RRC: RADIO BEARER RECONFIGURATION COMPLETE

UE

IubUu

All data is sent andRLC-U buffer is empty

Radio link release (NBAP) and AAL2 transmission release

[DCH] RRC: RADIO BEARER RECONFIGURATION

RLC-PDU transportation on DCH

UE in CELL_DCH state

Inactivity timer expires

UE in CELL_FACH state

Inactivity_ind

Inactivity_ind

Capacity_release


Physical Channels and Physical Channels and Physical Channels and Physical Channels and Mapping of Transport ChannelsMapping of Transport ChannelsMapping of Transport ChannelsMapping of Transport Channels


Frequency Division Duplex Frequency Division Duplex Frequency Division Duplex Frequency Division Duplex PPPPrinciplerinciplerinciplerinciple

Codes with different spreading, user bit rate 8 ÷ 384 kbps....

f

t10 ms frame

4.4-5 MHzHigh rate multicode user

Variable rate users

P (bit-rate)

Uplink

Dynamic rate matching for variable rate handling

Static Rate Matcing andDTX for variable rate handling

f

t10 ms frame

P (bit-rate)

Downlink

Tx–Rx frequency separation of 190 MHz

Advantagies of WCDMAAdvantagies of WCDMAAdvantagies of WCDMAAdvantagies of WCDMAWide 3.84 Mcps bandwidth (DS-CDMA) � good frequency & interferer diversity �low Eb/NoCoherent detection in both U/DL directions based on the use of pilot symbols � low Eb/NoFast power control (PC) � minimizes interference � high spectral efficiencyRobust RAKE diversity receiver � low complexityDynamic variable rate multiplexing � flexibility, BoD(Bandwidth on Demand)Supports the operation of asynchronous WCDMA BTSs


Dedicated PhCH StructureDedicated PhCH StructureDedicated PhCH StructureDedicated PhCH Structure

Superframe (720 ms)

#0 #1 #71Radio frame (10ms)

#0Slot (0.667 ms)

#14#2

SSSSystem ystem ystem ystem FFFFrame rame rame rame NNNNumberumberumberumber• Sent on BCH• Range 0 to 4095

Pilot TPC

DataDPDCH

DPCCH FBITFCIULULULULI/Q code multiplexed with I/Q code multiplexed with I/Q code multiplexed with I/Q code multiplexed with

complex scramblingcomplex scramblingcomplex scramblingcomplex scrambling

DataTFCI PilotData TPC

DPCCH DPCCHDPDCH DPDCH

DLDLDLDLTime multiplexed with complex scramblingTime multiplexed with complex scramblingTime multiplexed with complex scramblingTime multiplexed with complex scrambling

A pA pA pA physicalhysicalhysicalhysical channelchannelchannelchannel is defined by is defined by is defined by is defined by specific carrier frequency, code, and on the uplink, relative phspecific carrier frequency, code, and on the uplink, relative phspecific carrier frequency, code, and on the uplink, relative phspecific carrier frequency, code, and on the uplink, relative phase (0 or ase (0 or ase (0 or ase (0 or π/2π/2π/2π/2))))

UL DPDCH SF = 256 (15 ksps), 128, ..., 4 (960 ksps)

UL DPCCH SF = 256 (15 ksps)

DL DPCH SF = 512 (7.5 ksps), 256 (15 ksps), …, 4 (960 ksps)

UL DPDCH SF = 256 (15 ksps), 128, ..., 4 (960 ksps)

UL DPCCH SF = 256 (15 ksps)

DL DPCH SF = 512 (7.5 ksps), 256 (15 ksps), …, 4 (960 ksps)Note: in UL symbols/s = bits/sNote: in UL symbols/s = bits/sNote: in UL symbols/s = bits/sNote: in UL symbols/s = bits/s

Chip rate: 3.84Chip rate: 3.84Chip rate: 3.84Chip rate: 3.84 MchipsMchipsMchipsMchips/s/s/s/s �

1 Slot = 2560 chips

Chip rate: 3.84Chip rate: 3.84Chip rate: 3.84Chip rate: 3.84 MchipsMchipsMchipsMchips/s/s/s/s � 1 Time Slot = 2560 chipsEach two bits-pair (symbol) represents an I/Q pair of QPSK modulationSFN Cell System Frame Number is used for paging groups, system information scheduling etc. In FDD SFN = BFN adjusted with T_cell. Range: 0 to 4095 framesDedicated UplinkDedicated UplinkDedicated UplinkDedicated Uplink PhCHPhCHPhCHPhCH structurestructurestructurestructureFrame structure for one PC period (1 slot) - the DCHDCHDCHDCH is carried by this PhCHDPDCHDPDCHDPDCHDPDCH (Dedicated Physical Data Channel) (Dedicated Physical Data Channel) (Dedicated Physical Data Channel) (Dedicated Physical Data Channel) SF = 256/2SF = 256/2SF = 256/2SF = 256/2k k k k = 256 (15 ksps), 128, ..., 4 = 256 (15 ksps), 128, ..., 4 = 256 (15 ksps), 128, ..., 4 = 256 (15 ksps), 128, ..., 4 (960 ksps)(960 ksps)(960 ksps)(960 ksps)DPCCHDPCCHDPCCHDPCCH (Dedicated Physical Control Channel)(Dedicated Physical Control Channel)(Dedicated Physical Control Channel)(Dedicated Physical Control Channel) SF = 256 (15 ksps)SF = 256 (15 ksps)SF = 256 (15 ksps)SF = 256 (15 ksps)L1 control informationTFCITFCITFCITFCI = Transport Format Combination Indicator (UL radio frame CCTrCH parameters information)FBIFBIFBIFBI = Feedback Information between UE and UTRAN (L1: closed loop mode Tx Div and Site Selection Diversity SSDT)TPCTPCTPCTPC = Transmit Power Control symbols (DL inner loop PC commands)PilotPilotPilotPilot = Pilot symbols (channel estimation + coherent detection/averaging)I/Q multiplexed within each radio frame (no UL discontinuities) with complex scramblingDedicated DownlinkDedicated DownlinkDedicated DownlinkDedicated Downlink PhCHPhCHPhCHPhCH structurestructurestructurestructureFrame structure for one PC period - the DCHDCHDCHDCH is carried by the DPDCHWithin one downlink DPCH, dedicated data generated at Layer 2 and above, i.e. the dedicated transport channel (DCH), is transmitted in time-multiplex with control information generated at Layer 1 (known pilot bits, UL TPC commands, and an optional TFCI)The downlink DPCH can be seen as a time multiplex of a downlink time multiplex of a downlink time multiplex of a downlink time multiplex of a downlink DPDCHDPDCHDPDCHDPDCH and a downlink and a downlink and a downlink and a downlink DPCCHDPCCHDPCCHDPCCHDPCHDPCHDPCHDPCH SF = 512/2SF = 512/2SF = 512/2SF = 512/2k k k k = 5= 5= 5= 512 (7.5 ksps), 256 (15 ksps), …, 12 (7.5 ksps), 256 (15 ksps), …, 12 (7.5 ksps), 256 (15 ksps), …, 12 (7.5 ksps), 256 (15 ksps), …, 4 (960 ksps)4 (960 ksps)4 (960 ksps)4 (960 ksps)There are basically two types of downlink DPCHs• Those that include TFCI (e.g. for several simultaneous services)• And those that do not include TFCI (e.g. for fixed-rate services) In compressed modecompressed modecompressed modecompressed mode a different slot format (A, B) is used compared to normal mode


Multicode TransmissionMulticode TransmissionMulticode TransmissionMulticode Transmission• Ex. in the downlink

Transmission Power Physical Channel 1

Transmission Power Physical Channel 2

Transmission Power Physical Channel N

DPDCH

One Slot (2560 chips)

DPDCH

……………….

DPCCH DPCCH

TPC TFCI PilotData Data

Data Data

Data Data


Uplink Dedicated PhCHsUplink Dedicated PhCHsUplink Dedicated PhCHsUplink Dedicated PhCHsDPDCH fields

Slot Format #i Channel Bit Rate(kbps)

ChannelSymbol Rate

(ksps)

Services(kbps)

SF Bits/Frame

Bits/Slot

Ndata

0 15 15 256 150 10 101 30 30 128 300 20 202 60 60 12.2+3.4 64 600 40 403 120 120 28.8+3.4 32 1200 80 804 240 240 64+3.4 16 2400 160 1605 480 480 (12.2)+128+3.4 8 4800 320 3206 960 960 (12.2)+384+3.4 4 9600 640 640

DPCCH fields

SlotFormat

#i

Channel BitRate (kbps)

ChannelSymbol Rate

(ksps)

SF Bits/Frame

Bits/Slot

Npilot NTPC NTFCI NFBI Transmittedslots per

radio frame0 15 15 256 150 10 6 2 2 0 15

0A 15 15 256 150 10 5 2 3 0 10-140B 15 15 256 150 10 4 2 4 0 8-91 15 15 256 150 10 8 2 0 0 8-152 15 15 256 150 10 5 2 2 1 15

2A 15 15 256 150 10 4 2 3 1 10-142B 15 15 256 150 10 3 2 4 1 8-93 15 15 256 150 10 7 2 0 1 8-154 15 15 256 150 10 6 2 0 2 8-155 15 15 256 150 10 5 1 2 2 15

5A 15 15 256 150 10 4 1 3 2 10-145B 15 15 256 150 10 3 1 4 2 8-9

The channel bit and symbol rates in the table are the rates immediately before spreadingThe field order and the total n. of bits/slot are fixed, although the n. of bits per field may vary during a connection3.4 kbps is for mapping the DCCH (signalling)


Downlink Dedicated PhCHsDownlink Dedicated PhCHsDownlink Dedicated PhCHsDownlink Dedicated PhCHsDPDCH

Bits/SlotDPCCH

Bits/SlotSlot

Format#i

ChannelBit Rate(kbps)

ChannelSymbol Rate

(ksps)

Services(kbps)

SF Bits/Slot

NData1 NData2 NTPC NTFCI NPilot

Transmittedslots per radio

frameNTr

0 15 7.5 512 10 0 4 2 0 4 151 15 7.5 512 10 0 2 2 2 4 152 30 15 256 20 2 14 2 0 2 153 30 15 256 20 2 12 2 2 2 154 30 15 256 20 2 12 2 0 4 155 30 15 256 20 2 10 2 2 4 156 30 15 256 20 2 8 2 0 8 157 30 15 256 20 2 6 2 2 8 158 60 30 12.2+3.4 128 40 6 28 2 0 4 159 60 30 128 40 6 26 2 2 4 1510 60 30 128 40 6 24 2 0 8 1511 60 30 128 40 6 22 2 2 8 1512 120 60 28.8+3.4 64 80 12 48 4 8* 8 1513 240 120 (12.2)+64+3.4 32 160 28 112 4 8* 8 1514 480 240 (12.2)+128+3.4 16 320 56 232 8 8* 16 1515 960 480 (12.2)+384+3.4 8 640 120 488 8 8* 16 1516 1920 960 4 1280 248 1000 8 8* 16 15

* If TFCI bits are not used, then DTX shall be used in TFCI field

3.4 kbps is for mapping the DCCH (signalling)Multicode transmission = 1 DPCCH + n parallel DPDCH using different OVSF codes


Variable Rate HandlingVariable Rate HandlingVariable Rate HandlingVariable Rate Handling on DPCHson DPCHson DPCHson DPCHs• Uplink

• Downlink

DPCCHDPCCHDPCCHDPCCH DPDCHDPDCHDPDCHDPDCH

Maximum bit rate of that connectionMaximum bit rate of that connectionMaximum bit rate of that connectionMaximum bit rate of that connection

10 ms frame

Lower bit rate (discontinuous transmission) Lower bit rate (discontinuous transmission) Lower bit rate (discontinuous transmission) Lower bit rate (discontinuous transmission)

............

DPCCHDPCCHDPCCHDPCCH

DPDCHDPDCHDPDCHDPDCH

Lower bit rate Higher bit rate Medium bit rate

10 ms frame 10 ms frame 10 ms frame

UplinkUplinkUplinkUplinkDPDCH bit rate can change frame-by-frame (10 ms).Higher bit rate requires more transmission power.Continuous transmission regardless of the bit rate.Reduced audible interference to other equipment (nothing to do with normal interference, does not affect the spectral efficiency).GSM interference frequency ~217 Hz (=1/4.615 ms).Admission control in RNC allocates the TFCS and the minimum SF.The relative power level is such that for higher bit rates the power of DPCCH is higher, thus enabling more accurate channel estimation, and the overhead (DPDCH vs DPCCH power) of the DPCCH is still lower.

DownlinkDownlinkDownlinkDownlinkDPDCH bit rate can change frame-by-frame (10 ms).Rate matching done to the maximum bit rate of that connection.Lower bit rates obtained with discontinuous transmission (audible interference not a problem in downlink).Admission control allocates those bit rates that can be used on physical layer.No L1 DTX bits transmitted on the radio interface.


Common UplinkCommon UplinkCommon UplinkCommon Uplink PhCHPhCHPhCHPhCH (1/4)(1/4)(1/4)(1/4)• Physical Random Access Channel (Physical Random Access Channel (Physical Random Access Channel (Physical Random Access Channel (PRACHPRACHPRACHPRACH))))

• Slotted ALOHA approach with fast acquisition indication

#0 #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 #13 #14

5120 chips

radio frame: 10 ms radio frame: 10 ms

Access slot #0 Random Access TransmissionRandom Access TransmissionRandom Access TransmissionRandom Access Transmission

Access slot #1

Access slot #7

Access slot #14

Access slot #8

Random Access TransmissionRandom Access TransmissionRandom Access TransmissionRandom Access Transmission



Random Access Transmission

The random-access transmission is based on a Slotted ALOHA approach with fast acquisition indication. The UE can start the random-access transmission at the beginning of a number of well-defined time intervals, denoted access slots. There are 15 access slots per two frames and they are spaced 5120 chips apart. Information on what access slots are available for random-access transmission is given by higher layers.


Common UplinkCommon UplinkCommon UplinkCommon Uplink PhCHPhCHPhCHPhCH (2/4)(2/4)(2/4)(2/4)• RACHRACHRACHRACH subsubsubsub----channelschannelschannelschannels

• A RACH sub-channel defines a sub-set of the total set of uplink access slots

• There are a total of 12121212 RACH sub-channels

• RACH sub-channel #i (i = 0, …, 11) consists of the following uplink access slots• Uplink access slot #i leading by τp-a chips the downlink access slot #i contained within the

10 ms interval that is time aligned with P-CCPCH frames for which SFN mod 8 = 0 or SFNmod 8 = 1

• Every 12th access slot relative to this access slot

Sub-channel numberSFN modulo 8 ofcorrespondingP-CCPCH frame

0 1 2 3 4 5 6 7 8 9 10 11

0 0 1 2 3 4 5 6 71 12 13 14 8 9 10 112 0 1 2 3 4 5 6 73 9 10 11 12 13 14 84 6 7 0 1 2 3 4 55 8 9 10 11 12 13 146 3 4 5 6 7 0 1 27 8 9 10 11 12 13 14

Each cell is configured by RNP setting the preamble scrambling codepreamble scrambling codepreamble scrambling codepreamble scrambling code, the message message message message lengthlengthlengthlength in time (either 10 or 20 ms), the AICHAICHAICHAICH Transmission TimingTransmission TimingTransmission TimingTransmission Timing parameter (0 or 1, for setting the preamble-to-Acquisition Indicator distance), the set of available signaturessignaturessignaturessignatures and the set of available RACHRACHRACHRACH subsubsubsub----channels for each Access Service channels for each Access Service channels for each Access Service channels for each Access Service Class (Class (Class (Class (ASCASCASCASC)))).In order to provide different priorities of RACH usage when the RRC connection is set up, PRACH resources (access slots and preamble signatures) can be dividedbetween 8 different ASCs numbered from 0 (highest priority, used in case of Emergency Call or for reasons with equivalent priority) to 7 (lowest priority). If the UEis member of several ACs, then it selects the ASC for the highest AC number. AnASC defines a certain partition by RNP of the PRACH resources and is always associated with a persistence value computed by the terminal as a function of a dynamic persistence level (1-8) and a persistence-scaling factor (7 values, from 0-1 for ASC 2 – 7) set by RNP.


Common UplinkCommon UplinkCommon UplinkCommon Uplink PhCHPhCHPhCHPhCH (3/4)(3/4)(3/4)(3/4)• Structure of the PRACH message part

note: in UL symbols/s = bits/snote: in UL symbols/s = bits/snote: in UL symbols/s = bits/snote: in UL symbols/s = bits/s

Pilot Npilot bits

DataNdata bits

Tslot = 2560 chips, 10*2k bits (k=0..3)

Data

ControlTFCI

NTFCI bits SF = 256 (SF = 256 (SF = 256 (SF = 256 (15ksps15ksps15ksps15ksps))))

SF = 256, 128, 64, or 32SF = 256, 128, 64, or 32SF = 256, 128, 64, or 32SF = 256, 128, 64, or 32

AICH Access Slot

Pp-m

Message part...

Acquisition Indicator

AICH access slots RX at UE

PRACH access slots TX at UE

PreamblePower Ramp Step

Preamble Retrans Max

Preamble

Repetitions of a signature

(16161616 signatures signatures signatures signatures availableavailableavailableavailable)

10 ms or 20 ms10 ms or 20 ms10 ms or 20 ms10 ms or 20 ms

RACH max bit rate = 18 kbit/s (including L2 overhead) • PRACH ramping and message transmission

Structure of theStructure of theStructure of theStructure of the PRACHPRACHPRACHPRACH transmissiontransmissiontransmissiontransmissionThe message part length can be determined by L1 from the used signature and/or access slot, as configured by higher layers.Signatures, message length, and/or access slots (for which message length) assigned by higher layers.

PRACHPRACHPRACHPRACH preamble partpreamble partpreamble partpreamble partThe preamble consists of 256 repetitions of a signature of length 16 chips256 repetitions of a signature of length 16 chips256 repetitions of a signature of length 16 chips256 repetitions of a signature of length 16 chips (16x256 = 4096).There are a maximum of 16 available signatures16 available signatures16 available signatures16 available signatures, based on the Hadamard code set of length 16.

PRACHPRACHPRACHPRACH message partmessage partmessage partmessage partEach slot consists of two parts, a data part to which the RACHRACHRACHRACH transport channel is mapped and a control part that carries Layer 1 control information (data and control parts are transmitted in parallel)A 20 ms message part consists of two consecutive 10 ms message part radio frames• Data part SF = 256 (15 ksps), 128 (30 ksps), 64 (60 ksps), and Data part SF = 256 (15 ksps), 128 (30 ksps), 64 (60 ksps), and Data part SF = 256 (15 ksps), 128 (30 ksps), 64 (60 ksps), and Data part SF = 256 (15 ksps), 128 (30 ksps), 64 (60 ksps), and 32 (120 ksps)32 (120 ksps)32 (120 ksps)32 (120 ksps)• Control part SF = 256 (Control part SF = 256 (Control part SF = 256 (Control part SF = 256 (15ksps15ksps15ksps15ksps) ) ) ) note: in UL symbols/s = bits/snote: in UL symbols/s = bits/snote: in UL symbols/s = bits/snote: in UL symbols/s = bits/sThe control part consists of 8 known pilot bits to support channel estimation for coherent detectionThe TFCITFCITFCITFCI of a radio frame indicates the TFTFTFTF of the RACH transport channel mapped to the simultaneously transmitted message part radio frame (in case of a 20 ms 20 ms 20 ms 20 ms PRACHPRACHPRACHPRACH message message message message partpartpartpart, the TFCITFCITFCITFCI is repeatedis repeatedis repeatedis repeated in the second radio frame)


Common UplinkCommon UplinkCommon UplinkCommon Uplink PhCHPhCHPhCHPhCH (4/4)(4/4)(4/4)(4/4)• Structure of the PCPCH message part

Pilot TPC

Data

FBITFCI

Ts = 2560 chipsSF = 256 (SF = 256 (SF = 256 (SF = 256 (15ksps15ksps15ksps15ksps))))

SF = 256, 128, …, or 4SF = 256, 128, …, or 4SF = 256, 128, …, or 4SF = 256, 128, …, or 4

AP-AICH CD/CA-ICH

APs CD/CA

P0P1 P1

DPCCH (DL)

PCPCH (UL)0 or 8 slotsPower ControlPreamble

InformationandControl Data

Power Control, Pilot and CPCHcontrol commands

Ta

τ p-p τ p-cdp τ cdp-pcp

τ p-a1 τ a1-cdp τ cdp-a2 [Example shown is for Tcpch = 0]

T0

• Structure of the CPCH access transmission

The CPCH transmission is based on DSMA-CD approach with fast acquisition indication. The UE can start transmission at the beginning of a number of well-defined time-intervals, relative to the frame boundary of the received BCH of the current cell. The access slot timing and structure is identical to RACH. The PCPCH access transmission consists of one or several Access Preambles [A-P] of length 4096 chips, one Collision Detection Preamble (CD-P) of length 4096 chips, a DPCCH Power Control Preamble (PC-P) which is either 0 slots or 8 slots in length, and a message of variable length Nx10 ms.CPCH CPCH CPCH CPCH access preamble partaccess preamble partaccess preamble partaccess preamble partSimilar to RACH preamble part. The RACH preamble signature sequences are used. The number of sequences used could be less than the ones used in the RACH preamble. The scrambling code could either be chosen to be a different code segment of the Gold code used to form the scrambling code of the RACH preambles or could be the same scrambling code in case the signature set is shared.CCCCPCH collision detection preamble partPCH collision detection preamble partPCH collision detection preamble partPCH collision detection preamble partSimilar to RACH preamble part. The RACH preamble signature sequences are used. The scrambling code is chosen to be a different code segment of the Gold code used to form the scrambling code for the RACH and CPCH preambles.CPCH power control preamble partCPCH power control preamble partCPCH power control preamble partCPCH power control preamble partThe power control preamble segment is called the CPCH Power Control Preamble (PC-P) part. The Power Control Preamble length is a higher layer parameter, Lpc-preamble, which shall take the value 0 or 8 slots. CPCH message partCPCH message partCPCH message partCPCH message partEach message consists of up to N_Max_frames 10 ms frames. N_Max_frames is a higher layer parameter. Each 10 ms frame is split into 15 slots, each of length Tslot = 2560 chips. Each slot consists of two parts, a data part that carries higher layer information and a control part that carries Layer 1 control information. The data and control parts are transmitted in parallel. The spreading factor for the control part of the CPCH message part is 256. The data part consists has SF = 256, 128, 64, 32, 16, 8 or 4.


Common DownlinkCommon DownlinkCommon DownlinkCommon Downlink PhCHsPhCHsPhCHsPhCHs (1/4)(1/4)(1/4)(1/4)

#0 #1Radio frame (10ms)

#0

Slot (2560 chips)

#14#2

Pre-defined pilot sequence

20 bits

20*2k bits (k = 0, ....,6)

TFCI Data PilotsS-CCPCH

Any CPICH

20 bits

256 chips

Data only (18 bits)(Tx OFF)P-CCPCH

15 ks/s SF =256 Cch,256,0 (P-CPICH)

15 ks/s SF =256Cch,256,1

15-960 ks/s SF =256-4

FACH max. bit rate = 36 kbps (including L2 overhead)

Common Pilot Channel (Common Pilot Channel (Common Pilot Channel (Common Pilot Channel (CPICHCPICHCPICHCPICH))))Physical channelPhysical channelPhysical channelPhysical channel, carries a pre-defined bit/symbol sequence at fixed rate (15 ksps, SF= 256)(15 ksps, SF= 256)(15 ksps, SF= 256)(15 ksps, SF= 256)Primary Common Pilot Channel (PPrimary Common Pilot Channel (PPrimary Common Pilot Channel (PPrimary Common Pilot Channel (P----CPICHCPICHCPICHCPICH))))The same channelization code is always used for this channel (CCCCchchchch,256,0,256,0,256,0,256,0).Scrambled by the primary scrambling code.There is one and only one P-CPICH per cell, which is broadcast over the entire cell.The Primary CPICH is a phase reference for the following downlink channels: SCH, Primary CCPCH, AICH, PICH AP-AICH, CD/CA-ICH, CSICH, DL-DPCCH for CPCH and the S-CCPCH. By default, the Primary CPICH is also a phase reference for downlink DPCH and any associated PDSCH. The UE is informed by higher layer signalling if the P-CPICH is not a phase reference for a downlink DPCH and any associated PDSCH.The Primary CPICH is always a phase reference for a DL PhCH using closed loop TX diversity.Secondary Common Pilot Channel (SSecondary Common Pilot Channel (SSecondary Common Pilot Channel (SSecondary Common Pilot Channel (S----CPICHCPICHCPICHCPICH))))An arbitrary channelization code of SF=256SF=256SF=256SF=256 is used for the S-CPICH.A S-CPICH is scrambled by either the primary or a secondary scrambling code.There may be zero, one, or several Szero, one, or several Szero, one, or several Szero, one, or several S----CPICHCPICHCPICHCPICH per cell.per cell.per cell.per cell.A S-CPICH may be transmitted over the entire cell or only over a part of the cell.over the entire cell or only over a part of the cell.over the entire cell or only over a part of the cell.over the entire cell or only over a part of the cell.A Secondary CPICH may be a phase reference for a downlink may be a phase reference for a downlink may be a phase reference for a downlink may be a phase reference for a downlink DPCHDPCHDPCHDPCH. If this is the case, the UE is

informed about this by higher-layer signalling.The Secondary CPICH can be a phase reference for a downlink physical channel using open loop TX

diversity, instead of the Primary CPICH being a phase reference.Primary Common Control Physical Channel (PPrimary Common Control Physical Channel (PPrimary Common Control Physical Channel (PPrimary Common Control Physical Channel (P----CCPCH)CCPCH)CCPCH)CCPCH)Is a fixed rate (15 ksps, SF = 25615 ksps, SF = 25615 ksps, SF = 25615 ksps, SF = 256) downlink physical channel used to carry the BCH.BCH.BCH.BCH.PPPPrimary CCPCHCCPCHCCPCHCCPCH the channelization code is fixed to CCCCchchchch,256,1.,256,1.,256,1.,256,1.No TPC commands, no TFCI and no pilot bits are transmitted.P-CCPCH is broadcast over the entire cell.over the entire cell.over the entire cell.over the entire cell.It is not transmitted during the first 256 chips of each slot, where Primary SCH and Secondary SCH are transmitted.Primary CCPCH (BCH) can only have a fixed predefined transport format combination.Secondary Common Control Physical Channel (SSecondary Common Control Physical Channel (SSecondary Common Control Physical Channel (SSecondary Common Control Physical Channel (S----CCPCH)CCPCH)CCPCH)CCPCH)Is used to carry FACHFACHFACHFACH and PCHPCHPCHPCH, they can be mapped to the same S-CCPCH (same frame) or to separate Secondary CCPCHs.Secondary CCPCHCCPCHCCPCHCCPCH SF = 256/2SF = 256/2SF = 256/2SF = 256/2k k k k = = = = 256, …, 256, …, 256, …, 256, …, 4444 � Channel symbol rate 15, 15, 15, 15, …………, 960 ksps., 960 ksps., 960 ksps., 960 ksps.It is not inner-loop power controlled (FACH/S-CCPCH slow power control via Frame Protocol).It can support variable ratevariable ratevariable ratevariable rate (multiple transport format combinations) with the help of the TFCITFCITFCITFCI field included.Only transmitted when there is data available. The FACH and PCH can be mapped to the same or to separate Secondary CCPCHs.


Common DownlinkCommon DownlinkCommon DownlinkCommon Downlink PhCHsPhCHsPhCHsPhCHs (2/4)(2/4)(2/4)(2/4)• Synchronization Channels (SCH)Synchronization Channels (SCH)Synchronization Channels (SCH)Synchronization Channels (SCH)

Primary SCH

Secondary SCH

256 chips

2560 chips SCH radio frame (10 ms)

ac s i,0

ac p

acsi,1 acs

i,14

Slot #0 Slot #1 Slot #14

acp acp64 possible Code Sequences (i=1,…,64), for frame synchronization and scrambling code group detection

Same code for every cell in the network, for slot synchronisation

Physical channelPhysical channelPhysical channelPhysical channel used for cell searchIt consists of two sub-channels transmitted in parallel and modulated by the symbol a, which indicates the presence/absence of STTD encoding on the P-CCPCH.

Primary Primary Primary Primary SCHSCHSCHSCH (one code/slot)(one code/slot)(one code/slot)(one code/slot)

It consists of a modulated code of length 256 chips (Cp).

It is transmitted every slot.

It is the same for every cell in the system and allows DL slot synchronisation to the cell.

Secondary Secondary Secondary Secondary SCHSCHSCHSCH (one sequence/radio frame)(one sequence/radio frame)(one sequence/radio frame)(one sequence/radio frame)

It consists of repeatedly transmitting a (length 15) sequence of modulated codes of length 256 chips, the Secondary Synchronisation Codes (SSC).

The SSC is denoted csi,k, where i = 1, 2, …, 64 is the number of the scrambling code

group, and k = 0, 1, …, 14 is the slot number.

This sequence on the Secondary SCH allows DL frame synchronisation and indicates which of the code groups the cell downlink scrambling code belongs to (see cell search procedure).

Each SSC is chosen from a set of 16 different codes of length 256.


• Acquisition Indicator Channel (Acquisition Indicator Channel (Acquisition Indicator Channel (Acquisition Indicator Channel (AICHAICHAICHAICH))))


1024 chips

No transmission

AI part = 4096 chips, 32 real-valued symbols

20 ms

Reserved for future use by other physical channels

AS #0 AS #1 AS #i AS #1415 ks/s SF =256 15 ks/s SF =256 15 ks/s SF =256 15 ks/s SF =256

288 bits for paging indication 12 bits

One radio frame (10 ms)

Bits not transmitted and reserved for future use

15 ks/s SF =25615 ks/s SF =25615 ks/s SF =25615 ks/s SF =256The PICH is always associated with the S-CCPCH to which a PCHtransport channel is mapped

• Page Indicator Channel (Page Indicator Channel (Page Indicator Channel (Page Indicator Channel (PICHPICHPICHPICH))))

Acquisition Indicator Channel (Acquisition Indicator Channel (Acquisition Indicator Channel (Acquisition Indicator Channel (AICHAICHAICHAICH))))The AICH is a fixed rate physical channel (SF = 256)rate physical channel (SF = 256)rate physical channel (SF = 256)rate physical channel (SF = 256) used to indicate in a cell the reception by the base station of PRACH preambles (signatures). Once the base station has received a preamble, the same signature that has been detected on thePRACH preamble is then sent back to the UE using this channel. Higher layers are not involved in this procedure: a response from the RNC would be too slow in order to acknowledge a PRACH preamble. The AICH consists of a repeated sequence of 15 consecutive access slots (AS) of length repeated sequence of 15 consecutive access slots (AS) of length repeated sequence of 15 consecutive access slots (AS) of length repeated sequence of 15 consecutive access slots (AS) of length 5120 chips5120 chips5120 chips5120 chips. Each AS includes an Acquisition-Indicator (AI) part of 32 real-valued symbols.The base station as a function of the signature ssss detected on the PRACH preamble derives the symbols of the AI part. The computation may result in a positive acknowledge, negative acknowledge or no acknowledge at all, if the detected signature is not a member of the set of available signatures for all the ASCs for the corresponding PRACH. There can be up to 16 signatures acknowledged on AICH at the same time.The UE receives the AICH information (channelisation code, STTD indicator ad AICH transmission timing) from the system information broadcast on BCH and accordingly starts receiving the AICH when the allocated PRACH is used. If the AICH or PICH information is not present, the terminal considers the cell barred and proceeds to cell re-selection.Page Indicator Channel (Page Indicator Channel (Page Indicator Channel (Page Indicator Channel (PICHPICHPICHPICH))))The PICH is a fixed rate (SF=256SF=256SF=256SF=256) physical channel used to carry the paging indicators.The PICH is always associated with an S-CCPCH to which a PCH transport channel is mapped.One PICH radio frame of length 10 ms consists of 300 bits (b0, b1, …, b299).288 bits (b0, b1, …, b287) are used to carry paging indicators.The remaining 12 bits are not formally part of the PICH and shall not be transmitted.The part of the frame with no transmission is reserved for possible future use.In each PICH frame are transmitted Np paging indicators, where Np is a cell based parameter, which can be set by RNP equal to 18 (16 bits are repeated), 36 (8 bits are repeated), 72 (4 bits are repeated), or 144 (only 2 bits are repeated). If a paging indicator in a certain frame is set to "1" it is an indication that UEs associated with this PI should read the corresponding frame of the associated S-CCPCH. Once a paging indicator has been detected, the UE decodes the S-CCPCH frame to see whether there was a paging message on PCHintended for it or not. The less often the page indicators appear in the frame the longer the UE battery life is.


• Physical Downlink Shared Channel (Physical Downlink Shared Channel (Physical Downlink Shared Channel (Physical Downlink Shared Channel (PDSCHPDSCHPDSCHPDSCH))))


TPCData 1 TFCI Data 2 Pilot

PO2PO3PO1

Timeslot (0.667 ms)

Downlinktransmission

power

time

Associated PDSCH data(not time aligned)

PDSCH power offset

DLDPCH

15151515----960 ks/s SF =256960 ks/s SF =256960 ks/s SF =256960 ks/s SF =256----4 4 4 4

32-512 kb/s (Turbo 1/3)

The Physical Downlink Shared Channel (PDSCH) is used to carry the Downlink Shared Channel (DSCH).A PDSCH corresponds to a channelisation code below or at a PDSCH root channelisation code. A PDSCH is allocated on a radio frame basis to a single UE. Within one radio frame, UTRAN may allocate different PDSCHs under the same PDSCH root channelisation code to different UEs based on code multiplexing. Within the same radio frame, multiple parallel PDSCHs, with the same spreading factor, may be allocated to a single UE. This is a special case of multicode transmission. All the PDSCHs are operated with radio frame synchronisation.PDSCHs allocated to the same UE on different radio frames may have different spreading factors.For each radio frame, each PDSCH is associated with one downlink DPCH. The PDSCH and associated DPCH do not necessarily have the same spreading factors and are not necessarily frame aligned.All relevant Layer 1 control information is transmitted on the DPCCH part of the associated DPCH, i.e. the PDSCH does not carry Layer 1 information. To indicate for UE that there is data to decode on the DSCH, the TFCI field of the associated DPCH is used.The TFCI informs the UE of the instantaneous transport format parameters related to thePDSCH as well as the channelisation code of the PDSCH.For PDSCH the allowed spreading factors may vary from 256 to 4256 to 4256 to 4256 to 4.The DSCH is always set up on top of a dedicated channel, which is used as a “return channel” for upper layer acknowledgesThe DL OLPC on DSCH is based on the associated DCH, when there is nothing to transmit on that DCH TBs with zero size are used and the UE can measure the BLER and adjust SIR target accordinglyBitRateDsch (Cell): 32, 64, 128, 256, 384, 512 kb/s TtiDsch (Cell): 10, 20 msChannel coding type: Turbo coding (1/3)


Cell Search ProcedureCell Search ProcedureCell Search ProcedureCell Search Procedure

SecondarySCH

PrimarySCH

P-CCPCH, (SFN modulo 2) = 0 P-CCPCH, (SFN modulo 2) = 1

Primary CPICH

10 ms

Slot synchronisation to a cell (cell selection using a matched filter)

Determination of the exact primary scrambling code used by the found cell (symbol-by-symbol correlation over the CPICH with all codes within the code group identified in the second step)

The Primary CCPCH is detected using the identified P-Scrambling Code �System- and cell specific BCH information can be read

Frame synchronisation and identification of the cell code group (correlation with all possible secondary synchronisation code sequences ⇔ 64 groups of 8 primary Scrambling Codes)

Slot synchronisationSlot synchronisationSlot synchronisationSlot synchronisationDuring the first step of the cell search procedure the UE uses the SCH’s primary synchronisation code to acquire slot synchronisation to a cell. This is typically done with a single matched filter (or any similar device) matched to the primary synchronisation code which is common to all cells. The slot timing of the cell can be obtained by detecting peaks in the matched filter output.Frame synchronisation and codeFrame synchronisation and codeFrame synchronisation and codeFrame synchronisation and code----group identificationgroup identificationgroup identificationgroup identificationDuring the second step of the cell search procedure, the UE uses the SCH’ssecondary synchronisation code to find frame synchronisation and identify the code group of the cell found in the first step. This is done by correlating the received signal with all possible secondary synchronisation code sequences, and identifying the maximum correlation value. Since the cyclic shifts of the sequences are unique the code group as well as the frame synchronisation is determined.ScramblingScramblingScramblingScrambling----code identificationcode identificationcode identificationcode identificationDuring the third and last step of the cell search procedure, the UE determines the exact primary scrambling code used by the found cell. The primary scrambling code is typically identified through symbol-by-symbol correlation over the CPICH with all codes within the code group identified in the second step. After the primary scrambling code has been identified, the Primary CCPCH can be detected.And the system- and cell specific BCH information can be read.


Compressed ModeCompressed ModeCompressed ModeCompressed ModeTransmission Gap Pattern SequenceTransmission Gap Pattern SequenceTransmission Gap Pattern SequenceTransmission Gap Pattern Sequence

TransmissionTransmission gap 2

gap 2

TGSN TGSN

TGL2 TGL2

TG pattern 2#TGPRC

gap 1Transmission Transmission

gap 1

TGD TGD

TGPL1 TGPL2

TG pattern 1 TG pattern 2

TGL1 TGL1

#1 #2 #3 #4 #5TG pattern 1TG pattern 1 TG pattern 2 TG pattern 1 TG pattern 2

Compressed ModeCompressed ModeCompressed ModeCompressed ModeState where at least one transmission gap pattern sequence (layer one parameterization unit, which contains one or two transmission gaps within a set of radio frames) is active. The aim of the downlink and uplink compressed mode is to allow the UE to monitor cells on other FDD frequencies and on other modes and radio access technologies that are supported by the UE, i.e. TDD and GSM.Instantaneous transmit power and the SIR target needs to be changed during the compressed frames, comparing to normal mode (for this purpose, the respective Delta SIRs are signaled by the RNC to the UE and to the WCDMA BTS).The methods for generating the compressed mode gaps are: rate matching, rate matching, rate matching, rate matching, reduction of the spreading factor by a factor of two and higher reduction of the spreading factor by a factor of two and higher reduction of the spreading factor by a factor of two and higher reduction of the spreading factor by a factor of two and higher layer schedulinglayer schedulinglayer schedulinglayer scheduling (in the downlink all methods are supported while compressed mode by rate matching is not used in the uplink).The maximum idle length is defined to be 7 slots per one 10 ms frame.


Timing and Synchronisation Timing and Synchronisation Timing and Synchronisation Timing and Synchronisation in UTRANin UTRANin UTRANin UTRAN----FDDFDDFDDFDD


Timing between Physical ChannelsTiming between Physical ChannelsTiming between Physical ChannelsTiming between Physical Channels

AICHAICHAICHAICHaccess slotsaccess slotsaccess slotsaccess slots

SecondarySecondarySecondarySecondarySCHSCHSCHSCH

PrimaryPrimaryPrimaryPrimarySCHSCHSCHSCH

tS-CCPCH,k

10 ms

tPICH

#0 #1 #2 #3 #14#13#12#11#10#9#8#7#6#5#4

PPPP----CCPCHCCPCHCCPCHCCPCH, (, (, (, (SFNSFNSFNSFN modulo 2) = 0modulo 2) = 0modulo 2) = 0modulo 2) = 0 PPPP----CCPCHCCPCHCCPCHCCPCH, (, (, (, (SFNSFNSFNSFN modulo 2) = 1modulo 2) = 1modulo 2) = 1modulo 2) = 1

AnyAnyAnyAny CPICHCPICHCPICHCPICH

k:k:k:k:thththth SSSS----CCPCHCCPCHCCPCHCCPCH

PICHPICHPICHPICH for k:for k:for k:for k:thththth SSSS----CCPCHCCPCHCCPCHCCPCH

n:n:n:n:th DPCHth DPCHth DPCHth DPCHtDPCH,n

AnyAnyAnyAny PDSCHPDSCHPDSCHPDSCH

PPPPPPPP--------CCPCHCCPCHCCPCHCCPCHCCPCHCCPCHCCPCHCCPCH is the timing reference is the timing reference is the timing reference is the timing reference is the timing reference is the timing reference is the timing reference is the timing reference for all the physical channels, for all the physical channels, for all the physical channels, for all the physical channels, for all the physical channels, for all the physical channels, for all the physical channels, for all the physical channels, directly for downlink and indirectly directly for downlink and indirectly directly for downlink and indirectly directly for downlink and indirectly directly for downlink and indirectly directly for downlink and indirectly directly for downlink and indirectly directly for downlink and indirectly for uplinkfor uplinkfor uplinkfor uplinkfor uplinkfor uplinkfor uplinkfor uplink

PPPPPPPP--------CPICHCPICHCPICHCPICHCPICHCPICHCPICHCPICH is the phase reference for is the phase reference for is the phase reference for is the phase reference for is the phase reference for is the phase reference for is the phase reference for is the phase reference for “all” downlink physical channels“all” downlink physical channels“all” downlink physical channels“all” downlink physical channels“all” downlink physical channels“all” downlink physical channels“all” downlink physical channels“all” downlink physical channels

tS-CCPCH,k = Tk × 256 chip, Tk ∈ {0, 1, …, 149}

tPICH = 7680 chips

tDPCH,n = Tn × 256 chip, Tn ∈ {0, 1, …, 149}Chip Offset

The cell SFN is transmitted on the P-CCPCH, which is used as timing reference for all physical channels, since the transmission timing in the uplink is derived from the timing of the downlink physical channels.The SCH (primary and secondary), CPICH (primary and secondary), P-CCPCH, andPDSCH have identical frame timing. The S-CCPCH timing may be different for different S-CCPCHs, but the offset from the P-CCPCH frame timing is a multiple of 256 chips. The PICH timing is 7680 chips prior to its corresponding S-CCPCH frame timing, i.e. the timing of the S-CCPCH carrying the PCH transport channel with the corresponding paging information. The AICH access slots #0 starts at the same time as P-CCPCH frames with (SFN modulo 2) = 0. The DPCH timing may be different for different DPCHs, but the offset from the P-CCPCH frame timing is always a multiple of 256 chips


Transport Channel SynchronisationTransport Channel SynchronisationTransport Channel SynchronisationTransport Channel Synchronisation

BS -2 SFN-2

CFN 149 150 151 152 153148

BS -1 SFN-1 1171

CFN

RNC CFN 150 151 152 153147 148 149

DL Data Frame

DL Radio Frame

UL Radio Frame

UL Data Frame

UE DL CFN 149 150 151 152 153147 148

Frame Offset

Frame Offset 1684 16891688168716861685

[CFN =150][CFN =150]

153152151150149148 147 117711761175117411731172

147 1683

Receiving Window

Frame arrows represent first chip or first bit in frames, TTI=10 ms, [FDD - Chip Offset = 0]

Frame Offsets of the different radio links are selected by the SRNC in order to have a timed transmission

The Transport Channel synchronisation, also presented as Layer 2 synchronisation, provides a Layer 2 common frame numbering between UTRAN and UE, or better the frame synchronisation between the L2 entities in the UTRAN and in the UE. The common frame reference at Layer 2 is defined as Connection Frame Number (CFN). TheCFN is a unique number for each RRC connection, and it is specified as the frame counter used for the transport channel synchronisation between UE and UTRAN. A CFN value is associated to each TBS and it is passed together with the TBS through the MAC-L1 service access point. The duration of a CFN cycle (0-255 frames) is supposed to be longer than the maximum allowed transport delay between MAC and L1 . When used for PCH the range of theCFN is from 0 to 4095 frames.Other important (optionally frequency-locked) counters are the Node B Frame Number (BFN) and the RNC Frame Number (RFN). The BFN and RFN are, respectively the Node B and RNC common frame number counters, which range form 0 up to 4095 frames. The System Frame Number (SFN) is the cell System Frame Number counter, which ranges from 0 up to 4095 frames and it is sent on BCH. The SFN is used for scheduling the information transmitted in the cell. In FDD the SFN equals the BFN adjusted with the timing delay used for defining the start of SCH, CPICH and the downlink Scrambling Code(s) in the cell (T_cell in 3GPP). T_cell has been specified in 3GPP in order to avoid the overlapping of SCHs (collision of SCH bursts) in different cells belonging to the same base station. In other words, the SFN in a cell is supposed to be delayed T_cell chips with respect to the BFN. T_cell has a resolution (step size) of 256 chips and ranges form 0 up to 9. In TDD, the SFN is locked to the BFN (i.e. SFN = BFN).The CFN is not transmitted in the radio interface, but is mapped by Layer 1 to the SFN of the first radio frame used for the transmission of the TBS in question. As already mentioned in this section, the SFN is broadcast at Layer 1 in the BCH and the mapping between the CFN and the SFN is performed as a function of a radio link specific parameter, denoted Frame Offset in3GPP. The Frame Offset is computed by the SRNC and provided to the base station when the radio link is set up, where the mapping between Layer 2 and Layer 1 is performed as: SFNmod 256 = (CFN + Frame Offset) mod 256 (from L2 to L1); and CFN = (SFN - Frame Offset) mod 256 (from L1 to L2). The transport channel synchronisation mechanism is valid for all downlink transport channels. In case of soft handover, i.e. only for DCHs belonging to radio links of different radio link sets, the Frame Offsets of the different radio links are selected by the SRNC in order to have a timed transmission of the diversity branches on the radio interface. During soft handover theCFN allows the frame selection combining at Layer 2 in the uplink and the frame splitting in the downlink.


Radio Interface SynchronisationRadio Interface SynchronisationRadio Interface SynchronisationRadio Interface Synchronisation SRNC

UE

Node BSource cell

Node BTarget cell

Frame Offset + Chip Offset (NBAP)

OFFtarget+ Tmtarget (RRC)

DL DPCHAt initial RL

DL SFN (timing reference)

DL DPCHnom = TUETx – To

DOFF (RRC)

At HO

Frame_offset + Chip_offset (NBAP)DL DPCH

For downlink orthogonality Frame Offset + Chip Offset are rounded to closest 256 chip boundary

The Radio Interface Synchronisation assures that the UE gets the correct frames while receiving from several cells. When setting up the first RL the SRNC selects a default-offset value for the dedicated physical channel, denote (DOFF) in the fugure, which is then used to initialise the Frame Offset and Chip Offset in the base station, and to inform the UE when the frames in the downlink are expected. In order to average out the Iub traffic and the Node B processing load all services are scheduled by means of DOFF. In addition, DOFF is used to spread out the location of pilot symbols in the downlink in order to reduce the base station peak power, since pilot symbols are always transmitted at the fixed location within a slot. Before any intra-frequency diversity handover the UE is supposed to measure the timing difference between the uplink DPCH and the target cell SFN and to report it to the SRNC. The SRNC breaks this time difference into two parameters (Frame Offset and Chip Offset) and forwards the computed values to Node B. The Node B rounds the received Chip Offset to the closest 256 chips boundary value in order to maintain the downlink orthogonality in the cell (regardless of the spreading factor in use) and then uses it for the downlink DPCH transmission as offset relative to the P-CCPCH timing.The handover reference is the time instant TUETx -To, which denoted DL DPCHnom in the timing diagram. Where TUETx represents the time when the UE transmits the uplink DPCH, and To is the nominal difference between the first received DPCH finger (DL DPCHnom) and TUETx at UE (constant of 1024 chips). OFF and Tm are estimated by the UE according to the following equation: OFF + Tm = (SFNtarget – DL DPCHnom) mod 256 frames [chips], where OFF and Tm are expressed in Frames and chips, respectively.


Spreading, Scrambling and ModulationSpreading, Scrambling and ModulationSpreading, Scrambling and ModulationSpreading, Scrambling and Modulation


SpreadingSpreadingSpreadingSpreading

Data x Code

Data

Code

Code(pseudo noise)

Data

+1

+1

+1

+1

+1

Symbol

-1

-1

-1

-1

-1

Despreading

Spectrum

SymbolBPSK-modulated bit sequence of rate R

ChipChip

Spreading Factor (SF) = Number of chips per data symbol

One symbol duration

SF = 8 chips / SymbolSF = 8 chips / SymbolSF = 8 chips / SymbolSF = 8 chips / Symbol

The spreading concept is applied to physical channels and it consists of two operations. The first is the channelization operation, which transforms each data symbol into a number of chips; thus increasing the bandwidth of the signal. The number of chips per data symbol is called Spreading Factor (SF)Spreading Factor (SF)Spreading Factor (SF)Spreading Factor (SF). The second operation is the scrambling operation, where a scrambling code is applied on top of the spread signal.


Detecting own signal.Detecting own signal.Detecting own signal.Detecting own signal. CorrelatorCorrelatorCorrelatorCorrelator

Code

Data aftermultiplication

+1

+1

+1

-1

-1

-1

Own signal

+8

-8

Data afterIntegration

Code

Data aftermultiplication

+1

+1

+1

-1

-1

-1

Other signal

+8

-8

Data afterIntegration

Increased on av. By a factor of 8 (Processing Gain)Increased on av. By a factor of 8 (Processing Gain)Increased on av. By a factor of 8 (Processing Gain)Increased on av. By a factor of 8 (Processing Gain)


Scrambling and Channelization codesScrambling and Channelization codesScrambling and Channelization codesScrambling and Channelization codes• Channelisation Codes (Channelisation Codes (Channelisation Codes (Channelisation Codes (OVSFOVSFOVSFOVSF))))

• Used for transmission from a single source separation• DL: connections within 1 cell• UL: dedicated PhCHs from 1 UE

• Have orthogonality properties � reduced interference • Have different spreading factors (SF) � different symbol rates• Are a limited resource (in the downlink) � must be "managed"

• Scrambling CodesScrambling CodesScrambling CodesScrambling Codes• UL: separate different UEs• DL: separate different cells (sectors)• Have good interference averaging (correlation) properties• On top of spreading codes (transmission BW is not affected � no spreading effect)

+1+1+1+1

----1111Channelization code (Channelization code (Channelization code (Channelization code (OVSFOVSFOVSFOVSF))))

+1+1+1+1Scrambling codeScrambling codeScrambling codeScrambling code

----1111+1+1+1+1

----1111Combined codeCombined codeCombined codeCombined code

Channelisation Code(Spreading)

Scrambling Code(Scrambling)

DATA Chip Rate Chip Rate

(W)


Channelisation Codes (1/2)Channelisation Codes (1/2)Channelisation Codes (1/2)Channelisation Codes (1/2)• OOOOrthogonal VVVVariable SSSSpreading FFFFactors (OVSFOVSFOVSFOVSF) codes

SF = 2SF = 4

Cch,1,0 = (1)

Cch,2,0 = (1,1)

Cch,2,1 = (1,-1)

Cch,4,0 =(1,1,1,1)

Cch,4,1 = (1,1,-1,-1)

Cch,4,2 = (1,-1,1,-1)

Cch,4,3 = (1,-1,-1,1)

SF = 1

Lowest SFSpreading codes in the sub-tree

In the channelization process data symbols on I- and Q-branches are independently multiplied with an Orthogonal Variable Spreading Factor (OVSF) code.In 3GPP the OVSF codes used for different symbol rates are uniquely described asCch,SF,k, where SF is the spreading factor of the code and k is the code number (0 ≤k≤SF-1). Each level of the code tree defines the channelization codes of length SF, where SF is the spreading factor of the codes. The channelization codes have orthogonal properties, and are used for separating the information transmitted from a single source, i.e. different connections within one cell in the downlink, where the own interference is also reduced, and dedicated physical data channels from one UE in the reverse direction.In the downlink the OVSF codes in a cell are limited resources and need to be managed by the radio network controller, whereas in the reverse direction such a problem does not exist and each terminal autonomously manages the code tree. The orthogonal property is preserved across different symbol rates, but the selection of one OVSF code will “block” the sub tree. In other words, another physical channel may use a certain code in the tree if no other physical channel to be transmitted using the same code tree is using a code that is on an underlying branch, i.e. using a higher SF code generated from the intended spreading code to be used. For the same reason, a smaller SF code on the path to the root of the tree cannot be used. During the network operation, the code tree may become “fragmented” and a code reshuffling is then needed.


Channelisation Codes (2/2)Channelisation Codes (2/2)Channelisation Codes (2/2)Channelisation Codes (2/2)• Generation method

1Cch,1,0 =

��

��

�

−=�

�

��

�

−=�

�

��

�

1111

0,1,

0,1,

0,1,

0,1,

1,2,

0,2,

ch

ch

ch

ch

ch

ch

CC

CC

CC

( )

( )

( )

( )

( ) ( )

( ) ( )��

�

�

��

�

�

−

−

−

=

��

�

�

��

�

�

−−

−−

−++

−++

+

+

+

+

12,2,12,2,

12,2,12,2,

1,2,1,2,

1,2,1,2,

0,2,0,2,

0,2,0,2,

112,12,

212,12,

3,12,

2,12,

1,12,

0,12,

:::

nnchnnch

nnchnnch

nchnch

nchnch

nchnch

nchnch

nnch

nnch

nch

nch

nch

nch

CCCC

CCCCCCCC

CC

CCCC

Cch,SF,k

SF = spreading factor of the code k = code number, 0 ≤ k ≤ SF-1

The OVSF codes are only effective when the channels are perfectly synchronized at symbol level. The loss in cross-correlation, e.g. due to multi-path, is compensated by the additional scrambling operation. With the scrambling operation the real (I) and imaginary (Q) parts of the spread signal are further multiplied by a complex-valued scrambling code. As already pointed out, the scrambling codes are used to separate different cells in the downlink and different terminals in the uplink direction. They have good correlation properties (interference averaging) and are always used on top of the spreading codes, thus not producing any effect on the transmission bandwidth.


• DPCCHDPCCHDPCCHDPCCH////DPDCHDPDCHDPDCHDPDCH

UL Spreading and Modulation (1/2)UL Spreading and Modulation (1/2)UL Spreading and Modulation (1/2)UL Spreading and Modulation (1/2)I/Q code multiplexing (dual-channel QPSK modulation) to avoid audible interference if no UL data transmitted

Complex-valued scrambling operation to avoid BPSK-type modulation @ high bit-rate (DPDCH and DPCCHs leads to multicode transmission )

IΣ

j

Cd,1 βd

S dpch, n

I+jQ

DPDCH1

Q

S

Cd,3 βdDPDCH3

Cd,5 βdDPDCH5

Cd,2 βdDPDCH2

Cd,4 βdDPDCH4

Cd,6 βdDPDCH6

Cc βcDPCCH

Σ

Im{S}

Re{S}Splitreal &imag.parts

Pulse-shaping

Pulse-shaping

cos(ωt)

-sin(ωt)

• DPCCHDPCCHDPCCHDPCCH always spread by code CCCCcccc = = = = CCCCchchchch,256,0 ,256,0 ,256,0 ,256,0 where k = 0k = 0k = 0k = 0• DPDCHDPDCHDPDCHDPDCH1111 spread by code CCCCdddd,1,1,1,1 = = = = CCCCchchchch,SF,k,SF,k,SF,k,SF,k where k = SF/4k = SF/4k = SF/4k = SF/4 is the OVSF code number• MulticodeMulticodeMulticodeMulticode, all DPDCHs have spreading factors equal to 4444Short scrambling codesShort scrambling codesShort scrambling codesShort scrambling codes (assigned by upper layers , 2(assigned by upper layers , 2(assigned by upper layers , 2(assigned by upper layers , 224242424 codes)codes)codes)codes)Used if in the Node B multi-user detectors or interference cancellation receivers are usedLong scrambling codesLong scrambling codesLong scrambling codesLong scrambling codes (assigned by upper layers, 2(assigned by upper layers, 2(assigned by upper layers, 2(assigned by upper layers, 224242424 codes)codes)codes)codes)10 ms long (33338888400 chips400 chips400 chips400 chips with 3.84 Mcps). Used if in the BS a Rake receiver is usedThe DPCCHDPCCHDPCCHDPCCH////DPDCHDPDCHDPDCHDPDCH may be scrambled by either long or short scrambling codeseither long or short scrambling codeseither long or short scrambling codeseither long or short scrambling codes

• DPCCHDPCCHDPCCHDPCCH always spread by code CCCCcccc = = = = CCCCchchchch,256,0 ,256,0 ,256,0 ,256,0 where k = 0k = 0k = 0k = 0• DPDCHDPDCHDPDCHDPDCH1111 spread by code CCCCdddd,1,1,1,1 = = = = CCCCchchchch,SF,k,SF,k,SF,k,SF,k where k = SF/4k = SF/4k = SF/4k = SF/4 is the OVSF code number• MulticodeMulticodeMulticodeMulticode, all DPDCHs have spreading factors equal to 4444Short scrambling codesShort scrambling codesShort scrambling codesShort scrambling codes (assigned by upper layers , 2(assigned by upper layers , 2(assigned by upper layers , 2(assigned by upper layers , 224242424 codes)codes)codes)codes)Used if in the Node B multi-user detectors or interference cancellation receivers are usedLong scrambling codesLong scrambling codesLong scrambling codesLong scrambling codes (assigned by upper layers, 2(assigned by upper layers, 2(assigned by upper layers, 2(assigned by upper layers, 224242424 codes)codes)codes)codes)10 ms long (33338888400 chips400 chips400 chips400 chips with 3.84 Mcps). Used if in the BS a Rake receiver is usedThe DPCCHDPCCHDPCCHDPCCH////DPDCHDPDCHDPDCHDPDCH may be scrambled by either long or short scrambling codeseither long or short scrambling codeseither long or short scrambling codeseither long or short scrambling codes

UplinkUplinkUplinkUplink DPCCHDPCCHDPCCHDPCCH////DPDCHDPDCHDPDCHDPDCH SpreadingSpreadingSpreadingSpreadingReal-valued spread signalsspread signalsspread signalsspread signals are weighted by gain factorsgain factorsgain factorsgain factors, βc for DPCCH and βd for all DPDCHs (at every instant in time, at least one of the values βc and βd has the amplitude 1.0); the stream of real-valued chips on the I and Q-branches are then summed and treated as a complex-valued stream of chips. This complex-valued signal is then scrambled by the complexcomplexcomplexcomplex----valued scrambling codevalued scrambling codevalued scrambling codevalued scrambling code SSSSdpchdpchdpchdpch,n,n,n,nThe DPCCHDPCCHDPCCHDPCCH is always spread by code CCCCcccc = = = = CCCCchchchch,256,0 ,256,0 ,256,0 ,256,0 where k = 0.k = 0.k = 0.k = 0.When only one DPDCH is to be transmitted, DPDCHDPDCHDPDCHDPDCH1111 is spread by code CCCCdddd,1,1,1,1 = = = = CCCCchchchch,SF,k,SF,k,SF,k,SF,kwhere SF SF SF SF is the spreading factor of DPDCH1 and k= SF/4k= SF/4k= SF/4k= SF/4 is the OVSF code number.When more than one When more than one When more than one When more than one DPDCHDPDCHDPDCHDPDCH is to be transmitted, all DPDCHs have spreading factors is to be transmitted, all DPDCHs have spreading factors is to be transmitted, all DPDCHs have spreading factors is to be transmitted, all DPDCHs have spreading factors equal to 4: equal to 4: equal to 4: equal to 4: DPDCHn is spread by the the code CCCCdddd,n ,n ,n ,n = = = = CCCCchchchch,4,k,4,k,4,k,4,k , where kkkk = 1= 1= 1= 1 if n ∈ {1, 2}, kkkk = 3= 3= 3= 3if n ∈ {3, 4}, and kkkk = 2= 2= 2= 2 if n ∈ {5, 6}.Uplink spreadingUplink spreadingUplink spreadingUplink spreadingThe spreading factor on DPDCH may vary on a frame by frame basis. The UE provides the TFCI to allow data detection with a variable SF on the DPDCH.Uplink scrambling codesUplink scrambling codesUplink scrambling codesUplink scrambling codesAll uplink physical channels are subjected to scrambling with a complex-valued scrambling code (scrambling sequence). The transmission from different UEs are separated by the scrambling codes. Uplink scrambling codes are assigned by higher layers. In uplink direction there are two alternatives:Short scrambling codesShort scrambling codesShort scrambling codesShort scrambling codesIs 256 chips256 chips256 chips256 chips....Used if in the Node B multi-user detectors or interference cancellation receivers are used.Long scrambling codesLong scrambling codesLong scrambling codesLong scrambling codes10 ms frame length (33338484848400 chips00 chips00 chips00 chips with 3.84 Mcps).Used if in the Node B a Rake receiver is used.The DPCCHDPCCHDPCCHDPCCH////DPDCHDPDCHDPDCHDPDCH may be scrambled by either long or short scrambling codes.either long or short scrambling codes.either long or short scrambling codes.either long or short scrambling codes.

There are 222224242424 longlonglonglong and 222224242424 short uplink scrambling codes short uplink scrambling codes short uplink scrambling codes short uplink scrambling codes � No uplink code planning need No uplink code planning need No uplink code planning need No uplink code planning need (millions of codes available)(millions of codes available)(millions of codes available)(millions of codes available)


• PRACHPRACHPRACHPRACH (or(or(or(or PCPCHPCPCHPCPCHPCPCH) message part) message part) message part) message part

• The Random Access PreambleRandom Access PreambleRandom Access PreambleRandom Access Preamble code CCCCprepreprepre,n,n,n,n, is derived from a preamble scrambling code SSSSrrrr-pre,pre,pre,pre,nnnn, which is also constructed from the long scrambling sequences as a function of the function of the function of the function of the downlink primary scrambling code downlink primary scrambling code downlink primary scrambling code downlink primary scrambling code uuuused sed sed sed in the serving cellin the serving cellin the serving cellin the serving cell, and a preamble signature CCCCsigsigsigsig,s,s,s,s

UL Spreading and Modulation (2/2)UL Spreading and Modulation (2/2)UL Spreading and Modulation (2/2)UL Spreading and Modulation (2/2)

I

j

Cd βd Sr-msg, n

I+jQ

PRACH messagedata part

Q

SCc βc

PRACH messagecontrol part

Im{S}


Pulse-shaping

Pulse-shaping

cos(ωt)

-sin(ωt)

Preamble SignaturePreamble SignaturePreamble SignaturePreamble Signature s, 0000 ≤ ssss ≤ 15151515CCCCcccc = = = = CCCCchchchch,256,m,256,m,256,m,256,m where m = 16*ssss + 15

CCCCdddd = = = = CCCCchchchch,SF,m,SF,m,SF,m,SF,m where SF is the spreading factor used for the data part and m = SF*ssss/16

(Long SC)

PRACH PRACH PRACH PRACH message part and preamble codesmessage part and preamble codesmessage part and preamble codesmessage part and preamble codesThe preamble signaturepreamble signaturepreamble signaturepreamble signature s, 0000 ≤ ssss ≤ 15151515, points to one of the 16 nodes in the code-tree that corresponds to channelization codes of length 16.The sub-tree below the specified node is used for spreading of the message part.spreading of the message part.spreading of the message part.spreading of the message part.The control partcontrol partcontrol partcontrol part is spread with the channelization code Cc of spreading factor 256 in the lowest branch of the sub-tree, i.e. CCCCcccc = = = = CCCCchchchch,256,m,256,m,256,m,256,m where m = 16*ssss + 15.The data partdata partdata partdata part is spread by channelization code CCCCdddd = = = = CCCCchchchch,SF,m,SF,m,SF,m,SF,m and SF is the spreading factor used for the data part and m = SF*ssss/16.The PRACHPRACHPRACHPRACH message part is scrambled with a long scramblinglong scramblinglong scramblinglong scrambling code.code.code.code.

The scrambling code for the PRACHPRACHPRACHPRACH preamble partpreamble partpreamble partpreamble part is also constructed from the long scrambling sequences. The 8192 preamble scrambling codes are divided into 512 groups with 16 codes in each group for a one-to-one correspondence between the preamble scrambling code and the downlink primary scrambling code m used in the serving cell. The random access preamblerandom access preamblerandom access preamblerandom access preamble code Cpre,n, is derived from a preamble scrambling code Sr-pre,n and a preamble signature Csig,s.In one cell may be configured several RACHs/PRACHs and the available pairs of RACH and PRACHs and their respective parameters and codes are indicated in system information. The various PRACHs are distinguished either by employing different preamble scrambling codes, or by using a common scrambling code but distinct (non-overlapping) partitions of available signatures and available sub-channels.

PCPCHPCPCHPCPCHPCPCH message part and preamble codesmessage part and preamble codesmessage part and preamble codesmessage part and preamble codesThe spreading and scrambling of the PCPCH message part is similar to the one illustrated for the PRACH. The same observation is valid for the preamble codes used for PCPCH.


• All downlink physical channelsAll downlink physical channelsAll downlink physical channelsAll downlink physical channels

DL Spreading and Modulation (1/2)DL Spreading and Modulation (1/2)DL Spreading and Modulation (1/2)DL Spreading and Modulation (1/2)

IAny Any Any Any downlink downlink downlink downlink physical physical physical physical channel channel channel channel except except except except SCHSCHSCHSCH

SSSS➜➜➜➜

PPPPCch,SF,m

j

Sdl,n

Q

I+jQ S

ΣΣΣΣG1

G2

GP

GS

SSSS----SCHSCHSCHSCH

PPPP----SCHSCHSCHSCH

TTTTΣΣΣΣ

SSSS

Im{S}


Pulse-shaping

Pulse-shaping

cos(ωt)

-sin(ωt)One code tree per cell is used and the code tree under a single One code tree per cell is used and the code tree under a single One code tree per cell is used and the code tree under a single One code tree per cell is used and the code tree under a single scrambling code is then scrambling code is then scrambling code is then scrambling code is then shared between several usersshared between several usersshared between several usersshared between several users• PPPP----CPICHCPICHCPICHCPICH always spread by code CCCCchchchch ==== CCCCchchchch,256,0,256,0,256,0,256,0

• PPPP----CCPCHCCPCHCCPCHCCPCH always spread by code CCCCchchchch ==== CCCCchchchch,,,,256256256256,1,1,1,1

• MulticodeMulticodeMulticodeMulticode, all DPDCHs have the same SF (different SF allowed for different CCTrCHs)• The SF does not vary on a frame-by-frame basis (DTX on DPDCH is used)Long scrambling codes (assigned by upper layers, 2Long scrambling codes (assigned by upper layers, 2Long scrambling codes (assigned by upper layers, 2Long scrambling codes (assigned by upper layers, 218181818 ––––1 codes, 8192 in practice)1 codes, 8192 in practice)1 codes, 8192 in practice)1 codes, 8192 in practice)10 ms long (33338484848400 chips00 chips00 chips00 chips with 3.84 Mcps)Each cell is allocated 1 primary SC (trivial task, no planning needed)

One code tree per cell is used and the code tree under a single One code tree per cell is used and the code tree under a single One code tree per cell is used and the code tree under a single One code tree per cell is used and the code tree under a single scrambling code is then scrambling code is then scrambling code is then scrambling code is then shared between several usersshared between several usersshared between several usersshared between several users• PPPP----CPICHCPICHCPICHCPICH always spread by code CCCCchchchch ==== CCCCchchchch,256,0,256,0,256,0,256,0

• PPPP----CCPCHCCPCHCCPCHCCPCH always spread by code CCCCchchchch ==== CCCCchchchch,,,,256256256256,1,1,1,1

• MulticodeMulticodeMulticodeMulticode, all DPDCHs have the same SF (different SF allowed for different CCTrCHs)• The SF does not vary on a frame-by-frame basis (DTX on DPDCH is used)Long scrambling codes (assigned by upper layers, 2Long scrambling codes (assigned by upper layers, 2Long scrambling codes (assigned by upper layers, 2Long scrambling codes (assigned by upper layers, 218181818 ––––1 codes, 8192 in practice)1 codes, 8192 in practice)1 codes, 8192 in practice)1 codes, 8192 in practice)10 ms long (33338484848400 chips00 chips00 chips00 chips with 3.84 Mcps)Each cell is allocated 1 primary SC (trivial task, no planning needed)

Downlink Spreading and ModulationDownlink Spreading and ModulationDownlink Spreading and ModulationDownlink Spreading and ModulationA part from SCHs, each pair of two consecutive symbols is first serial-to-parallel converted and mapped onto I and Q branches. The I and Q branches are then spread to the chip rate by the same channelization code Cch,SF,m. The sequences of real-valued chips on the I and Q branch are then scrambled using a complex-valued scrambling code, denoted Sdl,n. The scrambling code is applied aligned with the scrambling code applied to the P-CCPCH, where the first complex chip of the spread P-CCPCH frame is multiplied with chip number zero of the scrambling code.After spreading, each physical downlink channel (except SCHs) is separately weighted by a weight factor, denoted Gi in the figure. The complex-valued P-SCH and S-SCH are separately weighted by weight factors Gp and Gs. All downlink physical channels are combined together using a complex addition and the resulting sequence generated by the spreading and scrambling processes is thenQPSK modulated.Downlink spreading codesDownlink spreading codesDownlink spreading codesDownlink spreading codesIn the downlink the same channelization codes as in the uplink (OVSF codes) are used. Typically only one code tree per cell is used and the code tree under a single scrambling code is then shared between several users. By definition, the channelization code used for P-CPICH and P-CCPCH isCch,256,0 and Cch,256,1, respectively. Resource manager in the RNC assigns the channelization codes for all the other channels, with some restrictions on the usage of spreading factor 512 in case of diversity handover. In compressed mode there are three methods for generating gaps − rate matching, reduction of the spreading factor by a factor of two and higher layer scheduling. When the mechanism for opening the gap is by reducing the SF of 3 dB, the OVSF code used for compressed frames is Cch,SF/2,�n/2�, if an ordinary scrambling code is used; and Cch,SF/2,n mod SF/2, if an alternative scrambling code is used (see next slide), where Cch,SF,n is the channelization code used for non-compressed frames.In the downlink the SF of the DPCH does not vary on a frame-by-frame basis. The data rate variation on DPCH is managed with either a rate matching operation or with Layer 1 discontinuous transmission (DTX), where the transmission is interrupted during a part of the DPDCH slot. In case of multicode transmission, the parallel code channels have different channelisation codes, but equal spreading factor under the same scrambling code. Different spreading factors may be employed in case of several CCTrCHs received by the same UE. The OVSF code may vary from frame to frame on the PDSCH. The rule is such that the OVSF code(s) below the smallest spreading factor is from the branch of the code tree pointed by the smallest spreading factor used for that connection. If the DSCH is mapped onto multiple parallel PDSCHs, the same rule applies, but all branches identified by the multiple codes, corresponding to the smallest spreading factor, may be used for higher spreading factor allocation.


DL Spreading and Modulation (2/2)DL Spreading and Modulation (2/2)DL Spreading and Modulation (2/2)DL Spreading and Modulation (2/2)• Scrambling codeScrambling codeScrambling codeScrambling code

{ }

{ }

{ } dl,8191dlk,1768dl1,8177dl8176,

dl15,i*16dlk,i*16dl1,i*16dli,*16

dl15,dlk,dl2,dl1,dl0,

S ..., S ,..., S , S Set512 : :

S ..., S ,..., S , S Set16i+1 : :

S ..., S ,..., S , S , S Set1

++

+++

=

=

= ith set of 15 Secondary scrambling codes

{16*i+k} k=1, 2, …, 15 (Other PhCH ∈ ∈ ∈ ∈ Cell)

Group 1 (of 8 P-Scrambling Codes){16*( 8*0 +l)} I = 0, …, 7

Group 64 { 16*( 8*63+l)} I = 0, …, 7

Primary scrambling code i = 0, 1, …, 511

(P-CPICH, P-CCPCH, PICH, AICH, and S-CCPCH carrying PCH)

Group j {16*(8j+l)} l = 0, ...,7

j = 0, ..., 63

Note: the primary CCPCH, primary CPICH, PICH, AICH, and S-CCPCH carrying PCH are always transmitted using the primary scrambling code

Downlink scrambling codesIn the downlink only long scrambling codes are used. There are 222218181818----1 (= 262143)1 (= 262143)1 (= 262143)1 (= 262143)scrambling codes, numbered from 0 to 262142. The scrambling code sequences, denoted Sdl,n, are constructed as segments of the Gold sequence by combining two real sequences into a complex scrambling code sequence.In order to speed up the cell search procedure only 8192 codes of those are used in practice; and the phase pattern from 0 to 38399 is forcibly repeated, thus resulting in a periodical scrambling code of period 10 ms, which facilitates the UE in finding the correct code phase. Only the scrambling codes with k = 0, 1, …, 8191 can be employed. Those codes are divided into 512 sets. Each set consists of a primary scrambling code and 15 secondary scrambling codes, unambiguously associated the ones to the others, i.e. the ith primary scrambling code corresponds to ith set of secondary scrambling codes. The set of primary scrambling codes is further divided into 64 groups of 8 primary scrambling codes. Each primary scrambling code k is unambiguously associated with a left (denoted k + 8192) and a right alternative scrambling code (denoted k + 16384), which can be used for scrambling compressed frames, during the downlink compressed mode.Each cell is allocated one and only one primary scrambling code. The primaryCCPCH, primary CPICH, PICH, AICH, and S-CCPCH carrying PCH are always transmitted using the primary scrambling code. The allocation of primary scrambling codes is a trivial task and can be done with the aid of any planning tool. The other downlink physical channels can be transmitted with either the same primary scrambling code or using a secondary scrambling code taken from the set of codes associated with it. For one CCTrCH is allowed the mixture of primary and secondary scrambling codes. However, if the CCTrCH is type DSCH, then all PDSCHchannelisation codes received by a single UE must be under a single scrambling code.


Maximum Downlink Capacity (1/2)Maximum Downlink Capacity (1/2)Maximum Downlink Capacity (1/2)Maximum Downlink Capacity (1/2)

1/3 1/3 1/3 1/3 with 30%30%30%30% puncturingChannel coding rate for data

10%10%10%10%Average DPCCH overhead for data

QPSK, 2 2 2 2 bits/symbolModulation

3.84 McpsChip rate

128128128128Spreading factor for AMR

20%20%20%20%Soft HO overhead

10101010 codes with SF = 128Common Channels

AMR 12.2 kbps and one SC per cell


Maximum Downlink Capacity (2/2)Maximum Downlink Capacity (2/2)Maximum Downlink Capacity (2/2)Maximum Downlink Capacity (2/2)

QPSK modulation*2DPCCH overhead*0.91/3 rate channel coding/330% puncturing/(1-0.3)= 94*12.2*3*0.7/1000= 2.2.2.2.4444 MbpsMbpsMbpsMbps

Throughput

Speech full rate (AMR 12.2 kbps)

CCH and Soft HO overhead*(128-10)/128/1.25Chip rate3.84 106

= 99994444 channelschannelschannelschannelsSoft HO overhead/1.25CCH overhead*(128-10)/128

N. of codes with SF 128128 channels

AMR 12.2 kbps and one SC per cell

Part of the DL orthogonal codes must be reserved for the common channels and for soft and softer HO overhead. With this assumption the maximum number of speech calls per cell is 94 and the maximum data throughput is 2.4 Mbps.


High Speed Downlink Packet AccessHigh Speed Downlink Packet AccessHigh Speed Downlink Packet AccessHigh Speed Downlink Packet Access((((HSHSHSHS----DSCHDSCHDSCHDSCH))))


Achievable Achievable Achievable Achievable HSDPAHSDPAHSDPAHSDPA Peak Data RatesPeak Data RatesPeak Data RatesPeak Data Rates

QPSK

1/4

ModulationModulationModulationModulation Turbo Turbo Turbo Turbo code ratecode ratecode ratecode rate

2/4

3/4

16

SFSFSFSF

16

16

16QAM2/4

3/4

16

16

1.2 Mbps

ThroughputThroughputThroughputThroughput(10 codes)(10 codes)(10 codes)(10 codes)

2.4 Mbps

3.6 Mbps

4.8 Mbps

7.2 Mbps

1.8 Mbps

ThroughputThroughputThroughputThroughput(15 codes)(15 codes)(15 codes)(15 codes)

3.6 Mbps

5.3 Mbps

7.2 Mbps

10.7 Mbps

240

Bits/blockBits/blockBits/blockBits/block/code/code/code/code

470

711

950

1440

Basic block length is 2 ms corresponding to 3 time slots.Shown code rates are not accurate since transport block size will be semi-static. Hence, rate matching is used to fill out the TTI.64QAM has been suggested for HSDPA as well. However, due to performance and complexity issues, 64QAM may not be supported.16QAM with 15 multi-codes supports >10Mbps throughput.


HSHSHSHS----DSCH DSCH DSCH DSCH versus versus versus versus DSCHDSCHDSCHDSCH

TTI Size (link adaptation rate) 10 ms 2 ms

FEATURE DSCH HS-DSCH

Variable spreading factor (VSF) Yes No

Fast power control Yes No

Adaptive modulation and coding (AMC) No Yes

H-ARQ with soft combining/incremental redundancy No Yes

Multi-code operation (Yes) Yes (10)

Handover support Hard Hard/(FCS, Rel6?)

Support for Tx/Rx diversity or MIMO Tx/Rx Tx/Rx,(MIMO Rel 6?)

In HSDPA fast power control and variable SF are replaced by AMC and multicodescombined with H-ARQ. Additionally, HSDPA facilitates faster scheduling and link adaptation rate.


HSDPAHSDPAHSDPAHSDPA Protocol ArchitectureProtocol ArchitectureProtocol ArchitectureProtocol Architecture

L2

L1

HS-DSCH

FP

RLC

L2

L1

L2

L1

L2

L1

HS-DSCH

FP

IubIubIubIub IurIurIurIur

PHY

MAC

PHY

RLC

UuUuUuUu

MAC-hs

HS-DSCH

FPHS-DSCH

FP

MAC-c/sh

MAC-D

HS-DSCH FP (frame protocol)

UE Node B SRNC DRNC

SDUs to be transmitted are transferred from MAC-c/sh to the MAC-hs via the Iub interface.Hybrid ARQ, link adaptation & packet scheduling are included in MAC-hs and located in Node-B The possibility to connect directly the HS-DSCH user plane of the SRNC and Node B using the transport network, i.e. by-pass the DRNC for the HS-DSCH user plane, is under consideration


PPPPhysicalhysicalhysicalhysical----LLLLayer ayer ayer ayer SSSStructuretructuretructuretructure in Time Domainin Time Domainin Time Domainin Time Domain• Channelization codes at a fixed spreading factor SF=16• Multi-code transmission is allowed• The same scrambling code sequence is applied to all the

channelisation codes that form a single HS-DSCHCCTrCH

• Furthermore, multiple UEs may be assigned channelisation codes in the same TTI i.e. multiplexing of multiple UE’s in code-domain is allowed

• The length of the HS-DSCH TTI is 3333××××TTTTslotslotslotslot, , , , where Tslot is equal to 2560 chip (≈0.67 ms)

• The TTI for HS-DSCH is a static transport-format parameter

CCCCCTrCHCTrCHCTrCHCTrCH and transport channelsand transport channelsand transport channelsand transport channelsThere is only one CCTrCH of HS-DSCH type per UE. If there are several HS-DSCHtransport channels in an HS-DSCH CCTrCH, the transport format combinations are configured in such a way that for any transport format combination, there is a maximum of one transport channel having a transport format with one or more transport blocks. There is no need to balance the quality between several transport channels. As such, there is no need for static rate matching parameters. As for theDSCH of Release-99, flexible positions are assumed.


Channel Coding and ModulationChannel Coding and ModulationChannel Coding and ModulationChannel Coding and Modulation• Link AdaptationLink AdaptationLink AdaptationLink Adaptation

• TF, modulation scheme and code rate, can be selected based on the downlink channel quality

• The selection of transport format is done by the MAC-HS located in Node B and can be based on e.g.

• Channel-quality feedback reported by the UE, or • From the transmit power of an associated DPCH• Other methods may also be possible

TrBl

kco

ncat

enat

ion

CR

C a

ttach

men

t

Cod

e bl

ock

segm

enta

tion

Cha

nnel

Cod

ing

Phys

ical

cha

nnel

segm

enta

tion

Inte

rleav

ing

Phys

ical

cha

nnel

map

ping

PhC

H#1

PhC

H#2

Phys

ical

Lay

er H

ybrid

-AR

Qfu

nctio

nalit

y

Red

unda

ncy-

vers

ion

(RV)

par

amet

er

Transport block concatenation and code block segmentationTransport block concatenation and code block segmentationTransport block concatenation and code block segmentationTransport block concatenation and code block segmentationThe same transport block concatenation and code block segmentation as in Release-99 is used for HS-DSCH. However, Transport block concatenation is performed before CRCattachment since there is only one CRC per TTI. The maximum code block size for turbo coding is 5114.CRC AttachmentCRC AttachmentCRC AttachmentCRC AttachmentA CRC of size 24 bits is calculated and added per HS-DSCH TTI. The CRC polynomial is defined in 3G TS 25.212.Channel Coding Channel Coding Channel Coding Channel Coding HS-DSCH channel coding uses the existing rate 1/3 Turbo code and the existing Turbo code internal interleaver, as outlined in 3G TS 25.212. Other code rates are generated from the basic rate 1/3 Turbo code by applying rate matching by means of puncturing or repetition.PPPPhysicalhysicalhysicalhysical----layer Hybridlayer Hybridlayer Hybridlayer Hybrid----ARQ ARQ ARQ ARQ This functionality is an extension of the release 99 rate matching. The Hybrid-ARQfunctionality matches the number of bits at the output of the channel (turbo) coder to the total number of bits of the HS-DSCH physical channels. The Hybrid-ARQ functionality is controlled by the parameter RV (Redundancy Version), i.e. the exact set of bits at the output of the physical-layer Hybrid-ARQ functionality depends on the number of input bits, the number of output bits, and the RV parameter. Channel Coding for Control Channels Channel Coding for Control Channels Channel Coding for Control Channels Channel Coding for Control Channels Defined in previous slidesDTX indication bitsDTX indication bitsDTX indication bitsDTX indication bitsDTX insertion is not employed. Since only one transport channel per TTI is supported, the rate-matching algorithm is used to fill the available physical resource, instead of using DTX insertion.InterleavingInterleavingInterleavingInterleavingSince the HS-DSCH TTI is static, only one interleaving (corresponding to Release-99 2nd interleaving) is needed. The interleaver has to be adapted to 3 slots.For TDD, interleaving adaptation has to be done to the HS-DSCH TTI length.Physical channel mappingPhysical channel mappingPhysical channel mappingPhysical channel mappingThe bits can be mapped to multiple physical channels in the same way as in release'99.MMMModulation odulation odulation odulation Two types of modulations namely QPSK and 16QPSK and 16QPSK and 16QPSK and 16----QAMQAMQAMQAM may be applied for HS-DSCH.


Downlink Physical Channel StructureDownlink Physical Channel StructureDownlink Physical Channel StructureDownlink Physical Channel Structure

Downlink DPCH

Shared Control Channel #1

Shared Control Channel #2

Shared Control Channel #M

Node B UE

Choice of HybridChoice of HybridChoice of HybridChoice of Hybrid ARQARQARQARQ combining schemes combining schemes combining schemes combining schemes a) For a retransmission, the transport-block set is the same as for the initial transmission. This means that, for a retransmission, the number of information bits NINFO to be transmitted is the same as for the initial transmission. Furthermore, for a retransmission, the modulation scheme and the channelisation-code set, including the size of the channelisation-code set, and the transmission power, may be different compared to the initial transmission. This means that, for a retransmission, the number of available channel bits Nch may differ compared to the initial transmission. Even if the number of available channel bits Nch is the same, the set of channel bits may be different for the retransmission compared to the initial transmission (Incremental Redundancy).b) Regardless of the number of information bits NINFO, channel coding is done using a Turbo code with rate Rbasic = 1/3. Each retransmission may use a different redundancy version, where each redundancy version is a different subset of the coded bits. Each subset may contain a different number of bits. Chase combining corresponds to defining or using only a single redundancy version.Physical layer aspects of Hybrid ARQPhysical layer aspects of Hybrid ARQPhysical layer aspects of Hybrid ARQPhysical layer aspects of Hybrid ARQThe following signalling is needed to support Hybrid ARQ:Downlink Signaling•The HARQ information includes the Hybrid ARQ process identifier in the corresponding HS-DSCH TTI. •The HARQ information also includes information about the redundancy version of the transmission in the corresponding HS-DSCH TTI.Uplink SignalingFor communicating the HARQ acknowledgements, an 1-bit ACK/NACK indication is used in the uplink. PPPPhysicalhysicalhysicalhysical----channel structurechannel structurechannel structurechannel structureIt consists of a downlink DPCH and a number of SCCH-HSs. The number of SCCH-HSs can range from a minimum of one SCCH-HS (M=1) to a maximum of four SCCH-HSs (M=4).Shared Control ChannelShared Control ChannelShared Control ChannelShared Control ChannelFor each HS-DSCH TTI, each Shared Control Channel (SCCH-HS) carries HS-DSCH-related downlink signalling for one UE. The following information is carried on the SCCH-HS:Transport-format and Resource related Information (TFRI);The exact number of bits for the Hybrid-ARQ-related information is FFS


Downlink DPCHDownlink DPCHDownlink DPCHDownlink DPCH

• Example of coding of HSExample of coding of HSExample of coding of HSExample of coding of HS----DSCHDSCHDSCHDSCH Indicator (HI)Indicator (HI)Indicator (HI)Indicator (HI)• Pi indicates SCCH-HS #i (i ∈{1, 2, 3, 4})• P0 indicates that no SCCH-HS carries HS-DSCH-related

signalling information to the UE

P1 (+1 +1)P4 (-1 +1)

P3 (+1 –1)P2 (-1 –1)

P0 (0 0)

If a downlink DPCH is present, it carries an HS-DSCH Indicator (HI), in addition to non-HS-DSCH-related physical-layer signalling and DCH transport channels. The HI consists of two information bits that indicate the SCCH-HS that carries the HS-DSCH-related signalling for the corresponding UE. The HI is transmitted in every third slot. If no SCCH-HS carries HS-DSCH-related signalling to the UE, the HI is not transmitted (DTX). As an example, if the HI is transmitted as one QPSK symbol, the possible signalling points are as in the figure. The QPSK symbol carrying the HI is punctured on the DPDCH. However, the puncturing position is TBD.


Downlink Timing StructureDownlink Timing StructureDownlink Timing StructureDownlink Timing Structure

HI Downlink DPCH (“maximum

Downlink DPCH (“maximum late”) HI

Shared Control Channel

Tslot (0.67 ms)

HS-DSCH

3×Tslot (2 ms)

HS-DSCH TTI (2 ms)

τHS-DSCH-control=(5120+mx256)chips

HI

HI

The figure illustrates the timing structure for the HS-DSCH control signalling. The fixed time offset between the SCCH-HS information and the start of the corresponding HS-DSCH TTI equals τHS-DSCH-control(2*Tslot+m*256chips=(5120+m*256)chips where ). The time offset between the DL DPCH slot carrying the HI and the start of the SCCH-HS information can vary in the interval [0, Tslot] depending on the timing of the downlink DPCH. It may be noted that the start of the HI overlaps with the first slot of the SCCH-HS Figure 4 illustrates the two extreme cases of the timing of DPCH vs SCCH-HS.


HSHSHSHS----DSCH Uplink SignallingDSCH Uplink SignallingDSCH Uplink SignallingDSCH Uplink Signalling

• DPCCH-HS with SF=256 that is code multiplexed with the existing dedicated uplink physical channels

• The HS-DSCH related uplink signalling consists of • H-ARQ acknowledgement and • Channel quality indicator

In FDD, the HS-DSCH related uplink signalling uses DPCCH-HS with SF=256 that is code multiplexed with the existing dedicated uplink physical channels. The HS-DSCH related uplink signalling consists of H-ARQ acknowledgement and channel quality indicator.

HSHSHSHS----DSCHDSCHDSCHDSCH Associated Uplink Dedicated Control Channel Associated Uplink Dedicated Control Channel Associated Uplink Dedicated Control Channel Associated Uplink Dedicated Control Channel

The following information is carried on the HS-DSCH associated uplink dedicated control channel (DPCCH-HS):

HHHH----ARQ ARQ ARQ ARQ acknowledgment, acknowledgment, acknowledgment, acknowledgment, A 1-bit Ack/Nack indication is used for a H-ARQacknowledgement. The acknowledgement bit is repetition coded to 10 bits and transmitted in one slot. H-ARQ acknowledgement field is DTX’ed when there is no ACK/NACK information being sent.

Measurement feedback informationMeasurement feedback informationMeasurement feedback informationMeasurement feedback information

Measurement feedback information contains channel quality indicator that may be used to select transport format and resource by HS-DSCH serving Node-B. A [5]-bit channel quality indicator is coded and transmitted over two slots. The transmission cycle and timing for channel quality indicator is determined by UTRAN and signalled by higher layer. The channel quality indicator consists of a recommended TFRCprovided by the UE to Node-B. The recommended TFRC is chosen by the UE from a TFRC reference list. The ACK/NACK message is transmitted with a power offset ∆PAN relative to the Release '99 uplink DPCCH. The power offset ∆PAN is a higher-layer parameter.


WCDMA Radio Link Performance WCDMA Radio Link Performance WCDMA Radio Link Performance WCDMA Radio Link Performance IndicatorsIndicatorsIndicatorsIndicators


UEUEUEUE Measurement AbilitiesMeasurement AbilitiesMeasurement AbilitiesMeasurement Abilities• CPICH ECPICH ECPICH ECPICH Ecccc/N/N/N/N0000

• Received energy per chip divided by the power density in the band• Ec/N0 = RSCP/RSSI

• CPICH RSCPCPICH RSCPCPICH RSCPCPICH RSCP• Received Signal Code Power, the received power on one code

measured on the Primary CPICH• UTRA carrierUTRA carrierUTRA carrierUTRA carrier RSSIRSSIRSSIRSSI

• Received Signal Strength Indicator, the wide-band received power within the relevant channel bandwidth

• TrCH BLERTrCH BLERTrCH BLERTrCH BLER• Block Error Ratio for each TrCH having CRC

• UE Tx PowerUE Tx PowerUE Tx PowerUE Tx Power• Terminal transmission power

CPICH EcCPICH EcCPICH EcCPICH Ec/No /No /No /No Received energy per chip divided by the power density in the bandMeasurement performed on the Primary CPICHThe reference point for Ec/N0 is the antenna connector at the UEIf Tx diversity is applied on the Primary CPICH the received energy per chip (Ec) from each antenna shall be separately measured and summed together in [Ws] to a total received chip energy per chip on the Primary CPICH, before calculating the Ec/N0CPICH RSCPCPICH RSCPCPICH RSCPCPICH RSCP Received Signal Code PowerReceived Signal Code PowerReceived Signal Code PowerReceived Signal Code PowerThe received power on one code measured on the Primary CPICHThe reference point for the RSCP is the antenna connector at the UEIf Tx diversity is applied on the Primary CPICH the received code power from each antenna shall be separately measured and summed together in [W] to a total received code power on the Primary CPICHUTRA carrierUTRA carrierUTRA carrierUTRA carrier RSSIRSSIRSSIRSSI Received Signal Strength IndicatorReceived Signal Strength IndicatorReceived Signal Strength IndicatorReceived Signal Strength IndicatorThe wide-band received power within the relevant channel bandwidthMeasurement shall be performed on a UTRAN downlink carrierThe reference point for the RSSI is the antenna connector at the UEOther measurementsOther measurementsOther measurementsOther measurements• PCCPCH RSCP• GSM carrier RSSI• Transport channel BLER• UE transmitted power• SFN-CFN observed time difference• SFN-SFN observed time difference• UE Rx-Tx time difference• Observed time difference to GSM cell• UE GPS Timing of Cell Frames for LCS


UTRANUTRANUTRANUTRAN Measurement AbilitiesMeasurement AbilitiesMeasurement AbilitiesMeasurement Abilities• Received carrier powerReceived carrier powerReceived carrier powerReceived carrier power

• The wide-band received power within the UTRAN uplink carrier channel bandwidth in an UTRAN access point

• Transmitted carrier powerTransmitted carrier powerTransmitted carrier powerTransmitted carrier power• Ratio between the total transmitted power and the maximum transmission

power• Transmitted code powerTransmitted code powerTransmitted code powerTransmitted code power

• Transmitted power on one channelisation code on one given scrambling code on one given carrier

• SIR SIR SIR SIR Signal to Interference Ratio (defined in UL only)• SIRDPCCH = (RSCPDPCCH/ISCP)*SFDPCCH

• Eb/N0 = SIRDPCCH*[N+(βc/βd)2]*(RDPDCH/Ruser)*(βd/βc)2*(SFDPDCH/SFDPCCH) For a single bearer service, N = n. of channelisation codes

Received carrier powerReceived carrier powerReceived carrier powerReceived carrier powerThe wide-band received power within the UTRAN uplink carrier channel bandwidth in an UTRAN access pointThe reference point for the received carrier power measurements shall be the antenna connectorTransmitted carrier power Transmitted carrier power Transmitted carrier power Transmitted carrier power Ratio between the total transmitted power and the maximum transmission powerTotal transmission power is the mean power [W] on one carrier from one UTRAN access pointMaximum transmission power is the mean power [W] on one carrier from one UTRAN access point when transmitting at the configured maximum power for the cell (on any carrier transmitted from theUTRAN access point)The reference point for the transmitted carrier power measurement shall be the antenna connectorIn case of Tx diversity the transmitted carrier power for each branch shall be measuredTransmitted code powerTransmitted code powerTransmitted code powerTransmitted code powerTransmitted power on one channelisation code on one given scrambling code on one given carrier (on any DPCH transmitted from the UTRAN access point and shall reflect the power on the pilot bits of theDPCH)The reference point for the transmitted code power measurement shall be the antenna connectorIn case of Tx diversity the transmitted code power for each branch shall be measuredSIR Signal to Interference RatioSIR Signal to Interference RatioSIR Signal to Interference RatioSIR Signal to Interference RatioSIR = (RSCP/ISCP)*SF = Uplink Es/NoWhere RSCP, Received Signal Code Power, the received power on one code measured on the pilot bits; ISCP, Interference Signal Code Power, the interference on the received signal measured on the pilot bits; SF, Spreading Factor used on DPCCH (256). SIR is measured on DPCCH after RL combination in Node B; The reference point for the SIR is the antenna connector of the UEEb = (N*RSCPd+RSCPc)/Ru � Eb/N0 = RSCPd(N+(βc/ βd)2)*W/(Ru*ISCP) = SIRc*(Rd/Ru)(N+(βc/ βd)2)*(βd/ βc)2*(SFd/SFc).Other measurementsOther measurementsOther measurementsOther measurements• Transport channel BER• Physical channel BER• Round trip time• UTRAN GPS timing of cell frames for LCS• PRACH/PCPCH propagation delay• Acknowledged PRACH preambles• Detected PCPCH access preambles• Acknowledged PCPCH access preambles


Layer 1 ProcessingLayer 1 ProcessingLayer 1 ProcessingLayer 1 Processing


Maximal Ratio CombiningMaximal Ratio CombiningMaximal Ratio CombiningMaximal Ratio Combining of Symbolsof Symbolsof Symbolsof SymbolsTransmitted

symbolin a slot

• Depending on distance, medium and attenuation of path between UE andWCDMA BTS, channel can rotate signal to any phase and to any amplitude

• QPSK (pilot) symbols carry information in phase

• Energy splitted to many fingers �combining (Pilots for SIR estimation and Data symbols)

• Maximal ratio combining corrects channel phase rotation (for combining) and weights components with channel amplitude estimate

• Less bias in the signal power estimate after combining (noise cancel), a further benefit is achieved in averaging the combination upon pilot symbols on each slot

• Same method used also for antenna combining (BTS, UE) and softer handover (BTS) and soft/softer handover (UE)

finger #1

finger #2

finger #3

Receivedsymbol

+Noise

Combinedsymbol

+Residual noise

Modifiedwith

channelestimate

and relativedelay

compensation(for combining)

The chip duration is 260 ns � the WCDMA receiver can separate multipath components and combine them if the difference in path length is at least 78 m

GeneralGeneralGeneralGeneralThe delay profile extends from 1-3 µs in urban and suburban area; it can be more of 20 µ s in hilly areaThe chip duration is 260 ns � the WCDMA receiver can separate multipath components and combine them if the difference in path length is at least 78 mThe fast fading (signal cancellation) is due to the relative phase shift [difference in path (λ/2 = 7 cm) and reflection coefficients (boundary conditions)] of the different contributions arriving at the receiverThe response of a matched filter identifies the delay positions at which significant energy arrives, and the correlation receivers (RAKE fingers) are allocated to those peaksWithin each correlation receiver, the fast changing phase and amplitude values are tracked and removed (pilot symbols are used to sound the channel and provide an estimate of the momentary channel state for a particular finger, then the received symbol is rotated back, so as undo the phase rotation caused by the channel)The demodulated and phase-adjusted (data and pilots) symbols across all active fingers are combined (recovering the energy across all delay positions, Maximal Maximal Maximal Maximal Ratio CombiningRatio CombiningRatio CombiningRatio Combining) and presented to the decoder for further processingProcessing at the chip rate (correlator, code generator and matched filter) is done inASICs, whereas symbol level processing (channel estimator, phase rotator, combiner) is implemented by a DSPMultiple receiver antennas (including the softer HO case) can be accommodated in the same way as multiple paths received from a single antenna (separated busses are used): by just adding additional Rake fingers to the antennas (actually the same n. of CHE fingers are shared to the peaks belonging to different antennas)


RAKE Diversity ReceiverRAKE Diversity ReceiverRAKE Diversity ReceiverRAKE Diversity Receiver

Correlator

Channelestimator

Phaserotator

DelayEqualizer

Codegenerators

Finger 1

Finger 2

Finger 3

Σ I

Σ Q

I

Q

Combiner

I

Q

Digitized inputsamples

(from RF, I/Q branches)

Matchedfilter

Despreading and integration to user data symbols

Estimation of the state of the channel form pilot symbolsand channel effect removal

Compensation of the delay for the difference in the arrival times of the symbols in each finger

Addition of the channel compensated symbols �multipath diversity against fading

Determination and updating of the multipath delay profile of the channel

Timing (finger allocation)� assignment of the RAKE fingers to the largest peaks


Delay Profile Estimation with MF Delay Profile Estimation with MF Delay Profile Estimation with MF Delay Profile Estimation with MF

• Multipath propagation causes several peaks in matched filter (MF) output

• Allocate RAKE fingers to these peaks• Later: track and monitor the peaks

Node B

UE


Matched FilterMatched FilterMatched FilterMatched Filter

ΣΣΣΣIncomingserial data

Predefined(parallel) data (codes only)

Register 1

Register 2

When samples ofincoming serialdata are equal tobits of predefineddata, there is a maximum at filteroutput

Tap 127 Tap 126 Tap 0

Sample 127

Sample 126

Sample 0

• To make a successful despreading, code and data timing must be known

• The propagation delay profile can be detected e.g. by a matched filter

+1

-1


UL Receiver diversity (space diversity)UL Receiver diversity (space diversity)UL Receiver diversity (space diversity)UL Receiver diversity (space diversity)

Fading

= Antenna 1= Antenna 2

Time

Amplitude

Antenna RAKEcombining(MRC)

SRNC

RNC

Node B


DL Receiver diversity (space diversity)DL Receiver diversity (space diversity)DL Receiver diversity (space diversity)DL Receiver diversity (space diversity)

Fading

= Antenna 1= Antenna 2

Time

Amplitude

Antenna RAKEcombining(MRC)

SRNC

RNC

Node B

Documents

WCDMA UTRAN Interfaces and Protocol Stacks